Dosing & Uses

AdultPediatricGeriatric

Dosage Forms & Strength

levodopa/carbidopa/entacapone

tablet

  • 50mg/12.5mg/200mg
  • 75mg/18.75mg/200mg
  • 100mg/25mg/200mg
  • 125mg/31.25mg/200mg
  • 150mg/37.5mg/200mg
  • 200mg/50mg/200mg

Parkinson Disease

Substitute an equal levodopa dose with Stalevo as patient's dose at transfer

Maintenance: Titrate as necessary

Carbidopa should be 70-100 mg/day; not to exceed 200 mg/day

Not to exceed 8 tablets/day divided q4-8hr while awake

Food increases levodopa absorption

Monitor hepatic, hematopoietic, cardiovascular, renal function

Safety & efficacy not established

Parkinson Disease

Substitute an equal levodopa dose with Stalevo as patient's dose at transfer

Maintenance: Titrate as necessary

Carbidopa should be 70-100 mg/day; not to exceed 200 mg/day

Not to exceed 8 tablets/day divided q4-8hr while awake

Food increases levodopa absorption

Monitor hepatic, hematopoietic, cardiovascular, renal function

Next:

Interactions

Interaction Checker

and entacapone/levodopa/carbidopa

No Results

     activity indicator 
    No Interactions Found
    Interactions Found

    Contraindicated

      Serious - Use Alternative

        Significant - Monitor Closely

          Minor

            All Interactions Sort By:
             activity indicator 

            Contraindicated (8)

            • isocarboxazid

              isocarboxazid, levodopa. Mechanism: pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

              entacapone, isocarboxazid. Either increases effects of the other by pharmacodynamic synergism. Contraindicated. Both nonselective MAO inhibitors and entacapone inhibit catecholamine metabolism, leading to increased levels of catecholamines. Potential for dangerously high HR or BP.

            • lonafarnib

              entacapone will increase the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Lonafarnib is a sensitive CYP3A4 substrate. Coadministration with strong or moderate CYP3A4 inhibitors is contraindicated.

            • phenelzine

              phenelzine, levodopa. Mechanism: pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            • phenelzine

              entacapone, phenelzine. Either increases effects of the other by pharmacodynamic synergism. Contraindicated. Both nonselective MAO inhibitors and entacapone inhibit catecholamine metabolism, leading to increased levels of catecholamines. Potential for dangerously high HR or BP.

            • procarbazine

              procarbazine, levodopa. Mechanism: pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            • selegiline

              selegiline, levodopa. Mechanism: pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode. Concomitant therapy with selegiline and carbidopa-levodopa may be associated with severe orthostatic hypotension not attributable to carbidopa-levodopa alone.

            • selegiline transdermal

              selegiline transdermal, levodopa. Mechanism: pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            • tranylcypromine

              entacapone, tranylcypromine. Either increases effects of the other by pharmacodynamic synergism. Contraindicated. Both nonselective MAO inhibitors and entacapone inhibit catecholamine metabolism, leading to increased levels of catecholamines. Potential for dangerously high HR or BP.

              tranylcypromine, levodopa. Mechanism: pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            Serious - Use Alternative (34)

            • amisulpride

              amisulpride, levodopa. Either decreases effects of the other by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Avoid use of amisulpride, a dopamine receptor antagonist, with dopamine agonists.

            • aripiprazole

              aripiprazole decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • chlorpromazine

              chlorpromazine decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • clozapine

              clozapine decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • desvenlafaxine

              levodopa and desvenlafaxine both increase serotonin levels. Avoid or Use Alternate Drug.

            • droperidol

              droperidol decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • elacestrant

              entacapone will increase the level or effect of elacestrant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

            • fluphenazine

              fluphenazine decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • haloperidol

              haloperidol decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • iloperidone

              iloperidone decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • infigratinib

              entacapone will increase the level or effect of infigratinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

            • linezolid

              linezolid and levodopa both increase serotonin levels. Avoid or Use Alternate Drug. Linezolid may increase serotonin as a result of MAO-A inhibition. If linezolid must be administered, discontinue serotonergic drug immediately and monitor for CNS toxicity. Serotonergic therapy may be resumed 24 hours after last linezolid dose or after 2 weeks of monitoring, whichever comes first.

              linezolid, levodopa. Mechanism: pharmacodynamic synergism. Avoid or Use Alternate Drug. Risk of acute hypertensive episode.

            • loxapine

              loxapine decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • loxapine inhaled

              loxapine inhaled decreases effects of levodopa by pharmacodynamic antagonism. Contraindicated.

            • lurbinectedin

              entacapone will increase the level or effect of lurbinectedin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

            • macimorelin

              levodopa, macimorelin. unspecified interaction mechanism. Avoid or Use Alternate Drug. Drugs that may transiently elevate growth hormone (GH) concentrations may impact the accuracy of the macimorelin diagnostic test. Allow sufficient washout time of drugs affecting GH release before administering macimorelin.

            • methylene blue

              methylene blue and levodopa both increase serotonin levels. Avoid or Use Alternate Drug. Methylene blue may increase serotonin as a result of MAO-A inhibition. If methylene blue must be administered, discontinue serotonergic drug immediately and monitor for CNS toxicity. Serotonergic therapy may be resumed 24 hours after last methylene blue dose or after 2 weeks of monitoring, whichever comes first.

            • metoclopramide intranasal

              levodopa, metoclopramide intranasal. Either increases effects of the other by Other (see comment). Avoid or Use Alternate Drug. Comment: Avoid use of metoclopramide intranasal or interacting drug, depending on importance of drug to patient.

              metoclopramide intranasal, levodopa. dopaminergic effects. Avoid or Use Alternate Drug. Opposing effects of metoclopramide and the interacting drug on dopamine. Potential exacerbation of symptoms (eg, parkinsonian symptoms) or decreased therapeutic effects of metoclopramide.

              entacapone, metoclopramide intranasal. Either increases effects of the other by Other (see comment). Avoid or Use Alternate Drug. Comment: Avoid use of metoclopramide intranasal or interacting drug, depending on importance of drug to patient.

            • olanzapine

              olanzapine decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • olopatadine intranasal

              entacapone and olopatadine intranasal both increase sedation. Avoid or Use Alternate Drug. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment.

            • olopatadine intranasal

              levodopa and olopatadine intranasal both increase sedation. Avoid or Use Alternate Drug. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment.

            • omaveloxolone

              entacapone will increase the level or effect of omaveloxolone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If unavoidable, reduce omaveloxolone dose to 100 mg/day. Closely monitor for adverse effects. If adverse effects emerge, further reduce to 50 mg/day.

            • pacritinib

              entacapone will increase the level or effect of pacritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

            • paliperidone

              paliperidone decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • perphenazine

              perphenazine decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • pimozide

              pimozide decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • procarbazine

              procarbazine and levodopa both increase serotonin levels. Avoid or Use Alternate Drug.

            • prochlorperazine

              prochlorperazine decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • promethazine

              promethazine decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • quetiapine

              quetiapine decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • repotrectinib

              entacapone will increase the level or effect of repotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Discontinue strong or moderate CYP3A inhibitors and wait 3-5 elimination half-lives before initiating repotrectinib.

            • risperidone

              risperidone decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • ropeginterferon alfa 2b

              ropeginterferon alfa 2b and entacapone both increase Other (see comment). Avoid or Use Alternate Drug. Narcotics, hypnotics or sedatives can produce additive neuropsychiatric side effects. Avoid use and monitor patients receiving the combination for effects of excessive CNS toxicity.

            • thioridazine

              thioridazine decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            Monitor Closely (189)

            • abobotulinumtoxinA

              abobotulinumtoxinA increases effects of levodopa by pharmacodynamic synergism. Use Caution/Monitor. Use of anticholinergic drugs after administration of botulinum toxin-containing products may potentiate systemic anticholinergic effects.

            • acebutolol

              carbidopa increases effects of acebutolol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of acebutolol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • aclidinium

              aclidinium, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • alfuzosin

              carbidopa increases effects of alfuzosin by pharmacodynamic synergism. Use Caution/Monitor. Monitor for hypotension.

            • acrivastine

              acrivastine and entacapone both increase sedation. Use Caution/Monitor.

            • amifostine

              amifostine, levodopa. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration with blood pressure lowering agents may increase the risk and severity of hypotension associated with amifostine. When amifostine is used at chemotherapeutic doses, withhold blood pressure lowering medications for 24 hr prior to amifostine; if blood pressure lowering medication cannot be withheld, do not administer amifostine.

            • amiloride

              carbidopa increases effects of amiloride by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of amiloride by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • amisulpride

              amisulpride and entacapone both increase sedation. Use Caution/Monitor.

            • amlodipine

              carbidopa increases effects of amlodipine by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • amlodipine

              levodopa increases effects of amlodipine by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • apomorphine

              apomorphine and levodopa both increase dopaminergic effects. Use Caution/Monitor. Combination may enhance efficacy. Monitor for hypotension.

            • asenapine

              asenapine and entacapone both increase sedation. Use Caution/Monitor.

              carbidopa increases effects of asenapine by pharmacodynamic synergism. Use Caution/Monitor. Monitor for hypotension.

            • asenapine transdermal

              asenapine transdermal and entacapone both increase sedation. Use Caution/Monitor.

            • atenolol

              carbidopa increases effects of atenolol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • atenolol

              levodopa increases effects of atenolol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • atogepant

              entacapone will increase the level or effect of atogepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

            • atropine IV/IM

              atropine IV/IM, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • avapritinib

              avapritinib and entacapone both increase sedation. Use Caution/Monitor.

            • benazepril

              levodopa increases effects of benazepril by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of benazepril by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              benazepril, levodopa. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Additive hypotensive effects.

            • benzhydrocodone/acetaminophen

              benzhydrocodone/acetaminophen and entacapone both increase sedation. Use Caution/Monitor.

            • betaxolol

              carbidopa increases effects of betaxolol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • betaxolol

              levodopa increases effects of betaxolol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • bisoprolol

              levodopa increases effects of bisoprolol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of bisoprolol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • bosentan

              carbidopa increases effects of bosentan by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of bosentan by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • brexpiprazole

              brexpiprazole and entacapone both increase sedation. Use Caution/Monitor.

            • bumetanide

              carbidopa increases effects of bumetanide by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • brimonidine

              brimonidine and entacapone both increase sedation. Use Caution/Monitor.

            • brivaracetam

              brivaracetam and entacapone both increase sedation. Use Caution/Monitor.

            • bromocriptine

              bromocriptine and levodopa both increase dopaminergic effects. Use Caution/Monitor. Combining drugs may be therapeutic in patients with Parkinsonism and may allow for reduced levodopa doses. Dosages should be carefully titrated during concomitant treatment.

            • bumetanide

              levodopa increases effects of bumetanide by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • buprenorphine subdermal implant

              buprenorphine subdermal implant and entacapone both increase sedation. Use Caution/Monitor.

            • buprenorphine transdermal

              buprenorphine transdermal and entacapone both increase sedation. Use Caution/Monitor.

            • buprenorphine, long-acting injection

              buprenorphine, long-acting injection and entacapone both increase sedation. Use Caution/Monitor.

            • bupropion

              bupropion increases effects of levodopa by pharmacodynamic synergism. Use Caution/Monitor. There is a higher incidence of adverse reactions with concurrent use of bupropion with levodopa. Use small initial dosages and small, gradual dosage increases of bupropion.

            • candesartan

              levodopa increases effects of candesartan by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • capivasertib

              entacapone will increase the level or effect of capivasertib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce capivasertib dose if coadministered with moderate CYP3A inhibitors.

            • captopril

              levodopa increases effects of captopril by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              captopril, levodopa. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs lower blood pressure. Monitor blood pressure.

              carbidopa increases effects of captopril by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • carbonyl iron

              carbonyl iron decreases levels of levodopa by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Oral administration of iron salts should be separated from levodopa by at least 2 hours.

            • carvedilol

              carbidopa increases effects of carvedilol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • carvedilol

              levodopa increases effects of carvedilol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • chlorothiazide

              levodopa increases effects of chlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of chlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • chlorthalidone

              levodopa increases effects of chlorthalidone by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of chlorthalidone by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • clevidipine

              levodopa increases effects of clevidipine by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of clevidipine by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • clonidine

              levodopa increases effects of clonidine by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of clonidine by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • cyclizine

              cyclizine, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • doxazosin

              carbidopa increases effects of doxazosin by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • cyclopenthiazide

              levodopa increases effects of cyclopenthiazide by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • daridorexant

              entacapone will increase the level or effect of daridorexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Daridorexant dose should not exceed 25 mg per night when coadministered with moderate CYP3A4 inhibitors.

              entacapone and daridorexant both increase sedation. Modify Therapy/Monitor Closely. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment.

              levodopa and daridorexant both increase sedation. Modify Therapy/Monitor Closely. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment.

            • dicyclomine

              dicyclomine, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • difelikefalin

              difelikefalin and entacapone both increase sedation. Use Caution/Monitor.

            • difelikefalin

              difelikefalin and levodopa both increase sedation. Use Caution/Monitor.

            • dihydroergotamine intranasal

              dihydroergotamine intranasal and levodopa both increase serotonin levels. Use Caution/Monitor.

            • diltiazem

              levodopa increases effects of diltiazem by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • diphenhydramine

              diphenhydramine, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • dobutamine

              entacapone will increase the level or effect of dobutamine by decreasing metabolism. Use Caution/Monitor. Entacapone is a COMT inhibitor. Caution if coadministered with drugs metabolized by COMT. If coadministered, monitor for changes in heart rate, heart rhythm, and blood pressure.

            • dopamine

              entacapone will increase the level or effect of dopamine by decreasing metabolism. Use Caution/Monitor. Entacapone is a COMT inhibitor. Caution if coadministered with drugs metabolized by COMT. If coadministered, monitor for changes in heart rate, heart rhythm, and blood pressure.

            • doxazosin

              levodopa increases effects of doxazosin by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • droxidopa

              carbidopa decreases effects of droxidopa by decreasing metabolism. Use Caution/Monitor. Carbidopa, a peripheral dopa-decarboxylase inhibitor, could prevent the conversion of droxidopa to norepinephrine; increased droxidopa dose may be required.

            • enalapril

              carbidopa increases effects of enalapril by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of enalapril by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • epinephrine

              entacapone will increase the level or effect of epinephrine by decreasing metabolism. Use Caution/Monitor. Entacapone is a COMT inhibitor. Caution if coadministered with drugs metabolized by COMT. If coadministered, monitor for changes in heart rate, heart rhythm, and blood pressure.

            • eplerenone

              carbidopa increases effects of eplerenone by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • epinephrine inhaled

              entacapone will increase the level or effect of epinephrine inhaled by decreasing metabolism. Use Caution/Monitor. Entacapone is a COMT inhibitor. Caution if coadministered with drugs metabolized by COMT. If coadministered, monitor for changes in heart rate, heart rhythm, and blood pressure.

            • epinephrine racemic

              entacapone will increase the level or effect of epinephrine racemic by decreasing metabolism. Use Caution/Monitor. Entacapone is a COMT inhibitor. Caution if coadministered with drugs metabolized by COMT. If coadministered, monitor for changes in heart rate, heart rhythm, and blood pressure.

            • eplerenone

              levodopa increases effects of eplerenone by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • epoprostenol

              carbidopa increases effects of epoprostenol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of epoprostenol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • eprosartan

              levodopa increases effects of eprosartan by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • esmolol

              carbidopa increases effects of esmolol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • esmolol

              levodopa increases effects of esmolol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • ethacrynic acid

              carbidopa increases effects of ethacrynic acid by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of ethacrynic acid by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • felodipine

              carbidopa increases effects of felodipine by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of felodipine by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • fenoldopam

              levodopa increases effects of fenoldopam by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of fenoldopam by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • fentanyl

              fentanyl and entacapone both increase sedation. Use Caution/Monitor.

            • fosinopril

              carbidopa increases effects of fosinopril by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • fentanyl intranasal

              fentanyl intranasal and entacapone both increase sedation. Use Caution/Monitor.

            • fentanyl iontophoretic transdermal system

              fentanyl iontophoretic transdermal system and entacapone both increase sedation. Use Caution/Monitor.

            • fentanyl transdermal

              fentanyl transdermal and entacapone both increase sedation. Use Caution/Monitor.

            • ferric maltol

              ferric maltol decreases levels of levodopa by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Oral administration of iron salts should be separated from levodopa by at least 2 hours.

            • ferrous fumarate

              ferrous fumarate decreases levels of levodopa by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Oral administration of iron salts should be separated from levodopa by at least 2 hours.

            • ferrous gluconate

              ferrous gluconate decreases levels of levodopa by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

            • ferrous sulfate

              ferrous sulfate decreases levels of levodopa by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Oral administration of iron salts should be separated from levodopa by at least 2 hours.

            • finerenone

              entacapone will increase the level or effect of finerenone by affecting hepatic enzyme CYP2E1 metabolism. Modify Therapy/Monitor Closely. Monitor serum potassium during initiation and dosage adjustment of either finererone or moderate CYP3A4 inhibitors. Adjust finererone dosage as needed.

              entacapone will increase the level or effect of finerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor serum potassium during initiation and dosage adjustment of either finererone or weak CYP3A4 inhibitors. Adjust finererone dosage as needed.

            • food

              food decreases levels of levodopa by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Food with a high protein content may interfere with the absorption of levodopa.

            • fosinopril

              levodopa increases effects of fosinopril by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • fosphenytoin

              fosphenytoin decreases effects of levodopa by unknown mechanism. Use Caution/Monitor.

            • furosemide

              carbidopa increases effects of furosemide by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of furosemide by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • ganaxolone

              entacapone and ganaxolone both increase sedation. Use Caution/Monitor.

            • guanfacine

              carbidopa increases effects of guanfacine by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • gepirone

              entacapone will increase the level or effect of gepirone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce gepirone dose by 50% when used concomitantly with a moderate CYP3A4 inhibitor.

            • glycopyrrolate

              glycopyrrolate, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • glycopyrrolate inhaled

              glycopyrrolate inhaled, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • guanfacine

              levodopa increases effects of guanfacine by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • hydralazine

              levodopa increases effects of hydralazine by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of hydralazine by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • hydrochlorothiazide

              levodopa increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • hyoscyamine

              hyoscyamine, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • iloprost

              carbidopa increases effects of iloprost by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • hyoscyamine spray

              hyoscyamine spray, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • iloprost

              levodopa increases effects of iloprost by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • indapamide

              carbidopa increases effects of indapamide by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of indapamide by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • irbesartan

              carbidopa increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • iron dextran complex

              iron dextran complex decreases levels of levodopa by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Oral administration of iron salts should be separated from levodopa by at least 2 hours.

            • isradipine

              carbidopa increases effects of isradipine by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • isavuconazonium sulfate

              entacapone will increase the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

            • isoproterenol

              entacapone will increase the level or effect of isoproterenol by decreasing metabolism. Use Caution/Monitor. Entacapone is a COMT inhibitor. Caution if coadministered with drugs metabolized by COMT. If coadministered, monitor for changes in heart rate, heart rhythm, and blood pressure.

            • isradipine

              levodopa increases effects of isradipine by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • ketanserin

              levodopa increases effects of ketanserin by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • labetalol

              carbidopa increases effects of labetalol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of labetalol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • lefamulin

              entacapone will increase the level or effect of lefamulin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor for adverse effects if lefamulin is coadministered with moderate CYP3A inhibitors.

            • lisinopril

              carbidopa increases effects of lisinopril by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • levomilnacipran

              levomilnacipran and levodopa both increase serotonin levels. Modify Therapy/Monitor Closely.

            • lisinopril

              levodopa increases effects of lisinopril by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • losartan

              levodopa increases effects of losartan by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • lumateperone

              entacapone will increase the level or effect of lumateperone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce lumateperone dose to 21 mg/day if coadministered with moderate CYP3A4 inhibitors.

            • lurasidone

              lurasidone decreases effects of levodopa by pharmacodynamic antagonism. Use Caution/Monitor. Antipsychotics may diminish the therapeutic effect of anti-parkinson's agents; may increase risk of hypotension.

            • mavacamten

              entacapone will increase the level or effect of mavacamten by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Inititiation of weak CYP2C19 inhibitors may require decreased mavacamten dose.

              entacapone will increase the level or effect of mavacamten by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Inititiation of moderate CYP3A4 inhibitors may require decreased mavacamten dose.

            • meclizine

              meclizine, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • methyclothiazide

              carbidopa increases effects of methyclothiazide by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              levodopa increases effects of methyclothiazide by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • methyldopa

              methyldopa, levodopa. pharmacodynamic synergism. Use Caution/Monitor. Risk of additive hypotensive effects, and risk of toxic CNS effects such as psychosis.

              entacapone will increase the level or effect of methyldopa by decreasing metabolism. Use Caution/Monitor. Entacapone is a COMT inhibitor. Caution if coadministered with drugs metabolized by COMT. If coadministered, monitor for changes in heart rate, heart rhythm, and blood pressure.

            • metolazone

              carbidopa increases effects of metolazone by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • methylphenidate

              levodopa, methylphenidate. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Potential for additive CNS stimulation.

            • metoprolol

              carbidopa increases effects of metoprolol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • metyrosine

              carbidopa increases effects of metyrosine by pharmacodynamic synergism. Use Caution/Monitor. Monitor for hypotension.

            • minoxidil

              carbidopa increases effects of minoxidil by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • moexipril

              carbidopa increases effects of moexipril by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • nadolol

              carbidopa increases effects of nadolol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • nebivolol

              carbidopa increases effects of nebivolol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • nicardipine

              carbidopa increases effects of nicardipine by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • nifedipine

              carbidopa increases effects of nifedipine by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • nisoldipine

              carbidopa increases effects of nisoldipine by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • norepinephrine

              entacapone will increase the level or effect of norepinephrine by decreasing metabolism. Use Caution/Monitor. Entacapone is a COMT inhibitor. Caution if coadministered with drugs metabolized by COMT. If coadministered, monitor for changes in heart rate, heart rhythm, and blood pressure.

            • metoclopramide

              metoclopramide decreases levels of levodopa by pharmacodynamic antagonism. Use Caution/Monitor. Avoid combination if possible.

            • metolazone

              levodopa increases effects of metolazone by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • metoprolol

              levodopa increases effects of metoprolol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • midazolam intranasal

              midazolam intranasal, levodopa. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Concomitant use of barbiturates, alcohol, or other CNS depressants may increase the risk of hypoventilation, airway obstruction, desaturation, or apnea and may contribute to profound and/or prolonged drug effect.

            • minoxidil

              levodopa increases effects of minoxidil by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • moexipril

              levodopa increases effects of moexipril by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • nadolol

              levodopa increases effects of nadolol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • nebivolol

              levodopa increases effects of nebivolol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • nicardipine

              levodopa increases effects of nicardipine by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • nifedipine

              levodopa increases effects of nifedipine by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • nisoldipine

              levodopa increases effects of nisoldipine by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • norgestrel

              entacapone will increase the level or effect of norgestrel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Strong or moderate CYP3A4 inhibitors may increase systemic concentration of norgestrel, which may increase risk for adverse effects

            • oliceridine

              entacapone will increase the level or effect of oliceridine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. If concomitant use is necessary, may require less frequent oliceridine dosing. Closely monitor for respiratory depression and sedation and titrate subsequent doses accordingly. If inhibitor is discontinued, consider increase oliceridine dosage until stable drug effects are achieved. Monitor for signs of opioid withdrawal.

            • olmesartan

              levodopa increases effects of olmesartan by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • onabotulinumtoxinA

              onabotulinumtoxinA, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • oxybutynin transdermal

              oxybutynin transdermal decreases effects of levodopa by pharmacodynamic antagonism. Use Caution/Monitor.

            • palovarotene

              entacapone will increase the level or effect of palovarotene by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Avoid coadministration of palovarotene, a CYP3A substrate, with moderate CYP3A inhibitors. If unavoidable, reduce palovarotene dose by 50%.

            • papaverine

              papaverine decreases effects of levodopa by unknown mechanism. Use Caution/Monitor.

            • penbutolol

              levodopa increases effects of penbutolol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of penbutolol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • perindopril

              carbidopa increases effects of perindopril by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of perindopril by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • phenoxybenzamine

              carbidopa increases effects of phenoxybenzamine by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • phentolamine

              levodopa increases effects of phentolamine by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • phentolamine

              carbidopa increases effects of phentolamine by pharmacodynamic synergism. Use Caution/Monitor. Monitor for hypotension.

            • phenytoin

              phenytoin decreases effects of levodopa by unknown mechanism. Use Caution/Monitor.

            • pindolol

              carbidopa increases effects of pindolol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of pindolol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • polysaccharide iron

              polysaccharide iron decreases levels of levodopa by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Oral administration of iron salts should be separated from levodopa by at least 2 hours.

            • prazosin

              carbidopa increases effects of prazosin by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • pramipexole

              levodopa and pramipexole both increase dopaminergic effects. Use Caution/Monitor.

            • prazosin

              levodopa increases effects of prazosin by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • propantheline

              propantheline, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • propranolol

              levodopa increases effects of propranolol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of propranolol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • pyridoxine

              pyridoxine decreases levels of levodopa by increasing metabolism. Use Caution/Monitor.

            • quinapril

              carbidopa increases effects of quinapril by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • pyridoxine (Antidote)

              pyridoxine (Antidote) decreases levels of levodopa by increasing metabolism. Use Caution/Monitor. Interaction does not occur if carbidopa taken concurrently.

            • quinapril

              levodopa increases effects of quinapril by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • ramipril

              carbidopa increases effects of ramipril by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of ramipril by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • rasagiline

              rasagiline, levodopa. Mechanism: pharmacodynamic synergism. Modify Therapy/Monitor Closely. Risk of acute hypertensive episode.

            • sacubitril/valsartan

              carbidopa increases effects of sacubitril/valsartan by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • ropinirole

              levodopa and ropinirole both increase dopaminergic effects. Use Caution/Monitor.

            • sacubitril/valsartan

              levodopa increases effects of sacubitril/valsartan by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • sapropterin

              sapropterin, levodopa. Mechanism: unspecified interaction mechanism. Use Caution/Monitor. Case reports of combination causing convulsions, over-stimulation, or irritability.

            • selegiline transdermal

              selegiline transdermal and levodopa both increase serotonin levels. Modify Therapy/Monitor Closely.

            • silodosin

              carbidopa increases effects of silodosin by pharmacodynamic synergism. Use Caution/Monitor. Monitor for hypotension.

            • solriamfetol

              levodopa and solriamfetol both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • sotalol

              carbidopa increases effects of sotalol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of sotalol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • sparsentan

              entacapone will increase the level or effect of sparsentan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. No dosage adjustment needed. Monitor blood pressure, serum potassium, edema, and kidney function regularly if sparsentan is coadministered with moderate CYP3A4 inhibitors.

            • spironolactone

              carbidopa increases effects of spironolactone by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • spironolactone

              levodopa increases effects of spironolactone by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • sumatriptan intranasal

              sumatriptan intranasal and levodopa both increase serotonin levels. Use Caution/Monitor.

            • telmisartan

              levodopa increases effects of telmisartan by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • terazosin

              carbidopa increases effects of terazosin by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

              levodopa increases effects of terazosin by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • timolol

              levodopa increases effects of timolol by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of timolol by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • tiotropium

              tiotropium, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • torsemide

              carbidopa increases effects of torsemide by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • torsemide

              levodopa increases effects of torsemide by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • trandolapril

              levodopa increases effects of trandolapril by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of trandolapril by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • treprostinil

              levodopa increases effects of treprostinil by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of treprostinil by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • triamterene

              levodopa increases effects of triamterene by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

              carbidopa increases effects of triamterene by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            • valsartan

              levodopa increases effects of valsartan by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

            • verapamil

              carbidopa increases effects of verapamil by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

            Minor (21)

            • anticholinergic/sedative combos

              anticholinergic/sedative combos, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • atropine

              atropine, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • belladonna alkaloids

              belladonna alkaloids, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • belladonna and opium

              belladonna and opium, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • benztropine

              benztropine, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • darifenacin

              darifenacin, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • ferric maltol

              ferric maltol decreases levels of carbidopa by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

            • ferrous fumarate

              ferrous fumarate decreases levels of carbidopa by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

            • ferrous gluconate

              ferrous gluconate decreases levels of carbidopa by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

            • ferrous sulfate

              ferrous sulfate decreases levels of carbidopa by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

            • fesoterodine

              fesoterodine, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • flavoxate

              flavoxate, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • homatropine

              homatropine, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • ipratropium

              ipratropium, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • iron dextran complex

              iron dextran complex decreases levels of carbidopa by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

            • methscopolamine

              methscopolamine, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • oxybutynin

              oxybutynin, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • oxybutynin topical

              oxybutynin topical, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • oxybutynin transdermal

              oxybutynin transdermal, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            • polysaccharide iron

              polysaccharide iron decreases levels of carbidopa by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

            • scopolamine

              scopolamine, levodopa. Other (see comment). Minor/Significance Unknown. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

            Previous
            Next:

            Adverse Effects

            >10%

            Entacapone

            • Dyskinesia (25%)
            • Nausea (14%)
            • Diarrhea (10%)
            • Hyperkinesia (10%)
            • Urine discoloration (10%)

            1-10%

            Entacapone

            • Hypokinesia (9%), dizziness (8%), Fatigue (6%), hallucinations (1-4%), anxiety (2%), somnolence (2%), asthenia (2%), agitation (1%)
            • Increased sweating (2%)
            • Purpura (2%)
            • Abdominal pain (8%), constipation (6%), vomiting (4%), dry mouth (3%), dyspepsia (2%), flatulence (2%), taste perversion (1%), gastritis (1%)
            • Back pain (4%)
            • Dyspnea (3%)
            • Bacterial infection (1%)

            Frequency Not Defined

            Levodopa/Carbodopa

            • Edema
            • Agitation, anxiety, ataxia, bruxism, confusion, daytime somnolence decreased attention span, dyskinesia, dystonia, euphoria, insomnia, fainting, fatigue, increased trembling of hands, insouciance, malaise, memory loss, nightmares, nervousness, restlessness, trismus, vivid dreams
            • Alopecia, hot flushes, increased &/or dark perspiration, skin eruptions
            • Abdominal pain & discomfort, burning feeling in tongue, constipation, diarrhea, dysgeusia, dry mouth, dysphagia, hiccups, meteorism, sialorrhea, nausea, weight loss
            • Muscular spasms, muscular cramp
            • Hematuria, dark urine, incontinence, priapism, urine retention
            • Blurred vision, diplopia, dilated pupil, oculogyric problems

            Entacapone

            • Postural hypotension
            • Insomnia
            • Confusion
            Previous
            Next:

            Warnings

            Contradindications

            Hypersensitivity

            Concurrency with nonselective MAOIs (discontinue 2 weeks before starting treatment)

            Narrow-angle glaucoma

            Cautions

            Dopaminergic therapy in patients with Parkinson’s disease has been associated with hallucinations

            As with levodopa, treatment with this drug combination may increase possibility of upper gastrointestinal hemorrhage in patients with a history of peptic ulcer

            All patients should be observed carefully for development of depression with concomitant suicidal tendencies; patients with past or current psychoses should be treated with caution

            Patients with hepatic impairment should be treated with caution; as with levodopa, periodic evaluation of hepatic function is recommended during extended therapy

            Cases of severe rhabdomyolysis reported with entacapone when used in combination with carbidopa and levodopa; severe prolonged motor activity including dyskinesia may possibly account for rhabdomyolysis; most cases were manifested by myalgia and increased values of creatine phosphokinase (CPK) and myoglobin; some of the reactions also included fever and/or alteration of consciousness; it is also possible that rhabdomyolysis may be a result of syndrome related to withdrawal-emergent hyperpyrexia and confusion

            Drugs known to be metabolized by COMT, such as isoproterenol, epinephrine, norepinephrine, dopamine, dobutamine, alpha-methyldopa, apomorphine, isoetherine, and bitolterol should be administered with caution in patients receiving entacapone regardless of route of administration (including inhalation), as their interaction may result in increased heart rate, arrhythmia, and/or increased blood pressure

            Somnolence

            • Patients with Parkinson’s disease have reported suddenly falling asleep without prior warning of sleepiness while engaged in activities of daily living (including the operation of motor vehicles); some of these episodes resulted in accidents; although many of these patients reported somnolence while taking entacapone, some did not perceive warning signs, such as excessive drowsiness, and believed that they were alert immediately prior to the event; some of these events reported to occur up to one year after initiation of therapy
            • Falling asleep while engaged in activities of daily living reported to always occur in a setting of pre-existing somnolence, although patients may not give such a history; prescribers should reassess patients for drowsiness or sleepiness especially since some of the events occur well after start of treatment; prescribers should also be aware that patients may not acknowledge drowsiness or sleepiness until directly questioned about drowsiness or sleepiness during specific activities; patients who have already experienced somnolence and/or an episode of sudden sleep onset should not participate in these activities during treatment
            • Before initiating treatment, advise patients of potential to develop drowsiness and specifically ask about factors that may increase risk such as use of concomitant sedating medications and presence of sleep disorders; if a patient develops daytime sleepiness or episodes of falling asleep during activities that require active participation (eg, conversations, eating, etc.), therapy should ordinarily be discontinued; If decision is made to continue therapy, patients should be advised not to drive and to avoid other potentially dangerous activities; there is insufficient information to establish whether dose reduction will eliminate episodes of falling asleep while engaged in activities of daily living

            Hypotension, orthostatic hypotension, and syncope

            • Reports of syncope were generally more frequent in patients in both treatment groups who had had a prior episode of documented hypotension (although episodes of syncope, obtained by history, were themselves not documented with vital sign measurement); hypotension, orthostatic hypotension, and syncope are observed in patients treated with drugs that increase central dopaminergic tone including this drug

            Dyskinesia

            • Dyskinesia (involuntary movements) may occur or be exacerbated at lower dosages and sooner with this drug than with preparations containing only carbidopa and levodopa; occurrence of dyskinesias may require dosage reduction
            • Although decreasing the dose of levodopa may ameliorate dyskinesia, many patients in controlled trials continued to experience frequent dyskinesias despite a reduction in their dose of levodopa

            Compulsive behaviors

            • Postmarketing reports suggest that patients treated with anti-Parkinson medications can experience intense urges to gamble, increased sexual urges, intense urges to spend money uncontrollably, and other intense urges; patients may be unable to control these urges while taking one or more of the medications generally used for the treatment of Parkinson’s disease and which increase central dopaminergic tone, including entacapone taken with levodopa and carbidopa
            • In some cases, although not all, these urges were reported to have stopped when dose of anti-Parkinson medications was reduced or discontinued; because patients may not recognize these behaviors as abnormal it is important for prescribers to specifically ask patients or their caregivers about the development of new or increased gambling urges, sexual urges, uncontrolled spending or other urges while being treated with entacapone; physicians should consider dose reduction or stopping therapy if patient develops such urges while taking this medication

            Withdrawal-emergent hyperpyrexia and confusion

            • Cases of hyperpyrexia and confusion resembling neuroleptic malignant syndrome (NMS) reported in association with dose reduction or withdrawal of therapy with carbidopa, levodopa, and entacapone; however, in some cases, hyperpyrexia and confusion were reported after initiation of treatment with entacapone
            • Hyperpyrexia and confusion are uncommon but they may be life-threatening with a variety of features, including hyperpyrexia/fever/hyperthermia, muscle rigidity, involuntary movements, altered consciousness/mental status changes, delirium, autonomic dysfunction, tachycardia, tachypnea, sweating, hyper- or hypotension, and abnormal laboratory findings (eg, creatine phosphokinase elevation, leukocytosis, myoglobinuria, and increased serum myoglobin)
            • If a patient needs to discontinue or reduce daily dose, the dose should be decreased slowly, with supervision from a healthcare provider; specific methods for tapering entacapone have not been systematically evaluated

            Diarrhea and colitis

            • Typically, diarrhea presents within 4 to 12 weeks after entacapone is started, but may appear as early as first week and as late as many months after initiation of treatment; diarrhea may be associated with weight loss, dehydration, and hypokalemia
            • Postmarketing experience has shown that diarrhea may be sign of drug-induced microscopic colitis, primarily lymphocytic colitis; in these cases diarrhea has usually been moderate to severe, watery and non-bloody, at times associated with dehydration, abdominal pain, weight loss, and hypokalemia
            • In the majority of cases, diarrhea and other colitis-related symptoms resolved or significantly improved when entacapone treatment was stopped; in some patients with biopsy confirmed colitis, diarrhea had resolved or significantly improved after discontinuation of entacapone but recurred after retreatment with entacapone
            • If prolonged diarrhea suspected to be related to Stalevo, the drug should be discontinued and appropriate medical therapy considered; if cause of prolonged diarrhea remains unclear or continues after stopping entacapone, further diagnostic investigations including colonoscopy and biopsies should be considered

            Fibrotic complications

            • Cases of retroperitoneal fibrosis, pulmonary infiltrates, pleural effusion, and pleural thickening reported in patients treated with ergot-derived dopaminergic agents; these complications may resolve when drug is discontinued, but complete resolution does not always occur
            • Although these adverse reactions may be related to ergoline structure of these compounds, a possible causal role of nonergot-derived drugs (eg, entacapone, levodopa), which increase dopaminergic activity, has also been considered
            • The expected incidence of fibrotic complications is so low that even if entacapone caused these complications at rates similar to those attributable to other dopaminergic therapies, it is unlikely that it would have been detected in a cohort of the size exposed to entacapone during its clinical development; four cases of pulmonary fibrosis have been reported during clinical development of entacapone; 3 of these patients were also treated with pergolide and 1 with bromocriptine; the duration of treatment with entacapone ranged from 7 months to 17 months

            Drug interaction overview

            • Use caution with drugs metabolized by COMT
            • Dose adjustment may be required when coadministered with anti-hypertensive agents
            • Risk of hypertension and dyskinesia reported during concomitant use tricyclic antidepressants with carbidopa/levodopa
            • Efficacy of therapy reduced when coadministered with dopamine D2 receptor antagonists, isoniazid, phenytoin, papaverine and iron salts
            • Dose adjustment may be required with drugs that interfere with biliary excretion, glucuronidation and intestinal beta-glucuronidase
            • Dose adjustment may be required with drugs metabolized by CYP2C9 (eg, coumadin); monitor INR when initiating therapy in patients on coumadin
            Previous
            Next:

            Pregnancy & Lactation

            Pregnancy

            There are no adequate data on developmental risk associated with use of drug in pregnant women

            Animal data

            • In animals, administration of carbidopa-levodopa or entacapone during pregnancy was associated with developmental toxicity, including increased incidences of fetal malformations; estimated background risk of major birth defects and miscarriage in indicated population is unknown

            Lactation

            Levodopa has been detected in human milk after administration of carbidopa-levodopa; there are no data on presence of entacapone or carbidopa in human milk, effects of levodopa, carbidopa, or entacapone on breastfed infant, or on milk production; however, inhibition of lactation may occur because levodopa decreases secretion of prolactin; carbidopa and entacapone are excreted in rat milk; in lactating rat, oral administration of radiolabeled entacapone resulted in levels of entacapone and/or metabolites in milk up to 2 to 3 times that in plasma;

            Consider developmental and health benefits of breastfeeding along with mother’s clinical need for drug and any potential adverse effects on breastfed infant or from underlying maternal condition

            Pregnancy Categories

            A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

            B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

            C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

            D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

            X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

            NA: Information not available.

            Previous
            Next:

            Pharmacology

            Mechanism of Action

            Levodopa: Crosses blood-brain barrier & converts to dopamine

            Carbidopa: Inhibits decarboxylation or breakdown of peripheral levodopa

            Entacapone: Selective & reversible inhibitor of COMT

            Pharmacokinetics

            Absorption

            • levodopa: rapid
            • carbidopa: slightly slower than levodopa/entacapone
            • entacapone: rapid

            Peak plasma time

            • levodopa: 0.6-2.4 hr
            • carbidopa: 2.5-3.4 hr
            • entacapone: 1-1.2 hr

            Half Life

            • levodopa: 1.7 hr
            • carbidopa: 1.6-2 hr
            • entacapone: 0.8-1 hr

            Protein Bound

            • levodopa: 10-30%
            • carbidopa: 36%
            • entacapone: 98%

            Metabolites

            • levodopa: dopamine, homovanillic acid
            • carbidopa: alpha-methyl-3-methoxy-4-hydroxyphenyl propionic acid & alpha-methyl-3,4-dihydroxyphenylpropionic acid
            • entacapone: cis-isomer

            Elimination

            • levodopa: urine: 80-85%
            • carbidopa: 30% unchanged in urine
            • entacapone: Urine (10%); feces (90%)
            Previous
            Next:

            Images

            No images available for this drug.
            Previous
            Next:

            Patient Handout

            A Patient Handout is not currently available for this monograph.
            Previous
            Next:

            Formulary

            FormularyPatient Discounts

            Adding plans allows you to compare formulary status to other drugs in the same class.

            To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.

            Adding plans allows you to:

            • View the formulary and any restrictions for each plan.
            • Manage and view all your plans together – even plans in different states.
            • Compare formulary status to other drugs in the same class.
            • Access your plan list on any device – mobile or desktop.

            The above information is provided for general informational and educational purposes only. Individual plans may vary and formulary information changes. Contact the applicable plan provider for the most current information.

            Tier Description
            1 This drug is available at the lowest co-pay. Most commonly, these are generic drugs.
            2 This drug is available at a middle level co-pay. Most commonly, these are "preferred" (on formulary) brand drugs.
            3 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs.
            4 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            5 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            6 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            NC NOT COVERED – Drugs that are not covered by the plan.
            Code Definition
            PA Prior Authorization
            Drugs that require prior authorization. This restriction requires that specific clinical criteria be met prior to the approval of the prescription.
            QL Quantity Limits
            Drugs that have quantity limits associated with each prescription. This restriction typically limits the quantity of the drug that will be covered.
            ST Step Therapy
            Drugs that have step therapy associated with each prescription. This restriction typically requires that certain criteria be met prior to approval for the prescription.
            OR Other Restrictions
            Drugs that have restrictions other than prior authorization, quantity limits, and step therapy associated with each prescription.
            Additional Offers
            Email to Patient

            From:

            To:

            The recipient will receive more details and instructions to access this offer.

            By clicking send, you acknowledge that you have permission to email the recipient with this information.

            Email Forms to Patient

            From:

            To:

            The recipient will receive more details and instructions to access this offer.

            By clicking send, you acknowledge that you have permission to email the recipient with this information.

            Previous
            Medscape prescription drug monographs are based on FDA-approved labeling information, unless otherwise noted, combined with additional data derived from primary medical literature.