doxazosin (Rx)

Brand and Other Names:Cardura, Cardura XL

Dosing & Uses

AdultPediatricGeriatric

Dosage Forms & Strengths

tablet

  • 1mg
  • 2mg
  • 4mg
  • 8mg

tablet, extended release

  • 4mg
  • 8mg

Hypertension

1 mg PO qDay in AM or PM; may titrate by doubling daily dose up to 16 mg qDay based on blood pressure response; usual dosage range is 1-2 mg qDay; if therapy is discontinued for several days, initiate dose at 1 mg qDay and titrate using initial dosing regimen

Extended release: Not indicated for hypertension

Benign Prostatic Hyperplasia

Immediate release: 1 mg PO qDay; may titrate by doubling daily dose at 1-2 week intervals to maximum 8 mg/day

If therapy is discontinued for several days, initiate dose at 1 mg qDay and titrate using initial dosing regimen

Extended release: 4 mg PO qDay; may titrate based on response and tolerability every 3-4 weeks to 8 mg PO qDay

If therapy is discontinued for several days, initiate dose at 1 mg qDay and titrate using initial dosing regimen

Dosing Modifications

Hepatic impairment: Use with caution in mild-to-moderate hepatic dysfunction; do not use in severe impairment

Renal impairment: Labeling from manufacturer does not provide dosage adjustment information

Dosing Considerations

Give first dose and increase at bedtime to avoid syncope

Dosage Forms & Strengths

tablet

  • 1mg
  • 2mg
  • 4mg
  • 8mg

Hypertension (Off-label)

Immediate release: 1-4 mg PO once daily in AM or PM

Hypertension

Avoid use for hypertension; high risk of orthostatic hypotension (Beers criteria); if used, lower initial dosages and gradual adjustments are recommended

Immediate release: 0.5-16 mg PO once daily in AM or PM

Extended release: Not indicated for hypertension

Benign Prostatic Hyperplasia

Immediate release: 1-8 mg/day PO

Extended release: 4 mg/day PO initially at breakfast; may be increased to no more than 8 mg/day PO

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Interactions

Interaction Checker

and doxazosin

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              Serious - Use Alternative (4)

              • sildenafil

                sildenafil increases effects of doxazosin by pharmacodynamic synergism. Avoid or Use Alternate Drug. Risk of hypotension; separate sildenafil >25mg from alpha blocker by 4hr.

              • tamsulosin

                doxazosin, tamsulosin. Either increases effects of the other by additive vasodilation. Avoid or Use Alternate Drug. Risk of hypotension.

              • vardenafil

                vardenafil increases effects of doxazosin by pharmacodynamic synergism. Contraindicated. Risk of hypotension.

              • yohimbe

                yohimbe increases effects of doxazosin by pharmacodynamic synergism. Contraindicated.

              Monitor Closely (92)

              • acebutolol

                doxazosin and acebutolol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely. The severity and duration of hypotension following the first dose of doxozosin may be enhanced.

              • aceclofenac

                aceclofenac decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • acemetacin

                acemetacin decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • aldesleukin

                aldesleukin increases effects of doxazosin by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

              • alfuzosin

                alfuzosin and doxazosin both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • amifostine

                amifostine, doxazosin. 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.

              • amlodipine

                doxazosin and amlodipine both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • asenapine

                asenapine and doxazosin both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • aspirin

                aspirin decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • aspirin rectal

                aspirin rectal decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • aspirin/citric acid/sodium bicarbonate

                aspirin/citric acid/sodium bicarbonate decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • atenolol

                doxazosin and atenolol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.

              • avanafil

                avanafil increases effects of doxazosin by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

              • betaxolol

                doxazosin and betaxolol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.

              • bisoprolol

                doxazosin and bisoprolol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.

              • captopril

                captopril, doxazosin. Either increases effects of the other by Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Exaggerated first dose hypotensive response. Both drugs lower blood pressure. Monitor blood pressure.

              • carbidopa

                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.

              • carvedilol

                doxazosin and carvedilol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.

              • celecoxib

                celecoxib decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • celiprolol

                doxazosin and celiprolol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.

              • choline magnesium trisalicylate

                choline magnesium trisalicylate decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • clevidipine

                doxazosin and clevidipine both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • clonidine

                clonidine, doxazosin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Additive sympatholytic action may worsen sinus node dysfunction and atrioventricular (AV) block.

              • diclofenac

                diclofenac decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • diflunisal

                diflunisal decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • diltiazem

                doxazosin and diltiazem both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • duvelisib

                duvelisib will increase the level or effect of doxazosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration with duvelisib increases AUC of a sensitive CYP3A4 substrate which may increase the risk of toxicities of these drugs. Consider reducing the dose of the sensitive CYP3A4 substrate and monitor for signs of toxicities of the coadministered sensitive CYP3A substrate.

              • enalapril

                enalapril, doxazosin. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Exaggerated first dose hypotensive response.

              • esmolol

                doxazosin and esmolol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely. The severity and duration of hypotension following the first dose of doxozosin may be enhanced.

              • etodolac

                etodolac decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • felodipine

                doxazosin and felodipine both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • fenoprofen

                fenoprofen decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • flurbiprofen

                flurbiprofen decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • fosinopril

                fosinopril, doxazosin. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Exaggerated first dose hypotensive response.

              • ibuprofen

                ibuprofen decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • ibuprofen IV

                ibuprofen IV decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • iloperidone

                iloperidone increases effects of doxazosin by pharmacodynamic synergism. Use Caution/Monitor.

              • imidapril

                imidapril, doxazosin. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Exaggerated first dose hypotensive response.

              • indomethacin

                indomethacin decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • isradipine

                doxazosin and isradipine both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • ketoprofen

                ketoprofen decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • ketorolac

                ketorolac decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • ketorolac intranasal

                ketorolac intranasal decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • labetalol

                doxazosin and labetalol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.

              • levodopa

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

              • lisinopril

                lisinopril, doxazosin. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Exaggerated first dose hypotensive response.

              • lornoxicam

                lornoxicam decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • lurasidone

                lurasidone increases effects of doxazosin by Other (see comment). Use Caution/Monitor. Comment: Potential for increased risk of hypotension with concurrent use. Monitor blood pressure and adjust dose of antihypertensive agent as needed.

              • maraviroc

                maraviroc, doxazosin. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of orthostatic hypotension.

              • meclofenamate

                meclofenamate decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • mefenamic acid

                mefenamic acid decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • meloxicam

                meloxicam decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • metoprolol

                doxazosin and metoprolol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.

              • moexipril

                moexipril, doxazosin. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Exaggerated first dose hypotensive response.

              • moxisylyte

                doxazosin and moxisylyte both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • nabumetone

                nabumetone decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • nadolol

                doxazosin and nadolol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.

              • naproxen

                naproxen decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • nebivolol

                doxazosin and nebivolol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.

              • nicardipine

                doxazosin and nicardipine both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • nifedipine

                doxazosin and nifedipine both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • nirmatrelvir/ritonavir

                nirmatrelvir/ritonavir will increase the level or effect of doxazosin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor for increased bradycardia, hypotension, or dizziness. If needed, temporarily pause the antihypertensive drug.

              • nisoldipine

                doxazosin and nisoldipine both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • nitroglycerin rectal

                nitroglycerin rectal, doxazosin. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Observe for possible additive hypotensive effects during concomitant use. .

              • oxaprozin

                oxaprozin decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • oxymetazoline topical

                oxymetazoline topical increases and doxazosin decreases sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Effect of interaction is not clear, use caution. Use Caution/Monitor.

              • parecoxib

                parecoxib decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • penbutolol

                doxazosin and penbutolol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.

              • perindopril

                perindopril, doxazosin. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Exaggerated first dose hypotensive response.

              • phenoxybenzamine

                doxazosin and phenoxybenzamine both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • phentolamine

                doxazosin and phentolamine both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • pindolol

                doxazosin and pindolol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.

              • piroxicam

                piroxicam decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • prazosin

                doxazosin and prazosin both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • propranolol

                doxazosin and propranolol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely. The severity and duration of hypotension following the first dose of doxozosin may be enhanced.

              • pseudoephedrine

                pseudoephedrine decreases effects of doxazosin by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

              • quinapril

                quinapril, doxazosin. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Exaggerated first dose hypotensive response.

              • ramipril

                ramipril, doxazosin. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Exaggerated first dose hypotensive response.

              • salicylates (non-asa)

                salicylates (non-asa) decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • salsalate

                salsalate decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • silodosin

                doxazosin and silodosin both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • sotalol

                doxazosin and sotalol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely. The severity and duration of hypotension following the first dose of doxozosin may be enhanced.

              • sulfasalazine

                sulfasalazine decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • sulindac

                sulindac decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • tadalafil

                tadalafil increases effects of doxazosin by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

              • terazosin

                doxazosin and terazosin both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • timolol

                doxazosin and timolol both increase anti-hypertensive channel blocking. Modify Therapy/Monitor Closely.

              • tolfenamic acid

                tolfenamic acid decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • tolmetin

                tolmetin decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

              • trandolapril

                trandolapril, doxazosin. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Exaggerated first dose hypotensive response.

              • verapamil

                doxazosin and verapamil both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              • zotepine

                doxazosin and zotepine both increase anti-hypertensive channel blocking. Use Caution/Monitor.

              Minor (7)

              • brimonidine

                brimonidine increases effects of doxazosin by pharmacodynamic synergism. Minor/Significance Unknown.

              • butcher's broom

                doxazosin, butcher's broom. Either decreases effects of the other by Mechanism: pharmacodynamic antagonism. Minor/Significance Unknown.

              • ethanol

                doxazosin, ethanol. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension, esp. in Asian pts.

              • phenylephrine

                doxazosin, phenylephrine. Either decreases effects of the other by Mechanism: pharmacodynamic antagonism. Minor/Significance Unknown.

              • phenylephrine PO

                doxazosin, phenylephrine PO. Either decreases effects of the other by Mechanism: pharmacodynamic antagonism. Minor/Significance Unknown.

              • tizanidine

                tizanidine increases effects of doxazosin by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.

              • treprostinil

                treprostinil increases effects of doxazosin by pharmacodynamic synergism. Minor/Significance Unknown.

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              Adverse Effects

              >10%

              Dizziness (5-19%)

              Fatigue (8-12%)

              Headache (6-10%)

              1-10%

              Vertigo (7%)

              Upper respiratory tract infection (URTI) (5%)

              Edema (3-4%)

              Rhinitis (3%)

              Dyspnea (1-3%)

              Abdominal pain (2%)

              Hypotension (1-2%)

              Nausea (1-2%)

              Orthostatic hypotension (dose related) (0.3-2%)

              Anxiety (1%)

              Palpitations (1%)

              Postmarketing experience

              Autonomic Nervous System: Priapism

              Cardiovascular System: Cerebrovascular accidents, dizziness postural, myocardial infarction

              Central and Peripheral Nervous System: Hypoesthesia, paresthesia

              Endocrine System: Gynecomastia

              Gastrointestinal System: Gastrointestinal obstruction, vomiting

              General Body System: Fatigue, hot flushes, malaise

              Heart Rate/Rhythm: Bradycardia, cardiac arrhythmias

              Hematopoietic: Leukopenia, purpura, thrombocytopenia

              Liver/Biliary System: Abnormal liver function tests, hepatitis, hepatitis cholestatic, jaundice

              Musculoskeletal System: Muscle cramps, muscle weakness

              Psychiatric: Agitation, anorexia, nervousness

              Respiratory System: Bronchospasm aggravated

              Skin Disorders: Alopecia, urticaria, skin rash, pruritus

              Special Senses: Blurred vision, intraoperative Floppy Iris Syndrome

              Urinary System: Hematuria, micturition disorder, micturition frequency, nocturia, polyuria

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              Warnings

              Contraindications

              Hypersensitivity to doxazosin or other quinazolines

              Cautions

              Use with caution in liver disease or recent cerebrovascular accident (CVA)

              Rule out prostate cancer before initiating therapy

              May cause first-dose syncope or sudden loss of consciousness

              Risk of orthostatic hypotension (dose dependent)

              Potential for hypotension, dry mouth, and urinary complications in elderly

              Priapism (painful penile erection, sustained for hours and unrelieved by sexual intercourse or masturbation) rarely reported (probably less frequently than once in every several thousand patients), with alpha-1 antagonists, including doxazosin; because condition can lead to permanent impotence if not promptly treated, patients must be advised about seriousness of condition

              Concomitant use of other antihypertensives (additive hypotensive effects)

              Extended-release form not indicated for hypertension

              Concomitant administration of immediate-release form with a phosphodiesterase-5 (PDE-5) inhibitor can result in additive blood pressure lowering effects and symptomatic hypotension

              May increase the risk of heart failure by exacerbating underlying myocardial dysfunction by β1Receptor stimulation with increases in renin and aldosterone

              May cause CNS depression, which may impair ability to operate heavy machinery and performing tasks that require mental alertness

              Allergic reactions, including urticaria, rash, angioedema, pruritus, and respiratory symptoms may occur

              Intraoperative floppy iris syndrome reported in cataract surgery patients who received alph1-blocker therapy; discontinuing alpha-blocker therapy prior to surgery does not appear to be of benefit

              Decreases in white blood cells (WBC) and neutrophil count reported; WBC and neutrophil counts returned to normal following discontinuation of therapy

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              Pregnancy & Lactation

              Pregnancy

              Not indicated for use in females or for the treatment of hypertension; the limited available data in pregnant women are not sufficient to inform a drug-associated risk for major birth defects and miscarriage; no adverse developmental outcomes were observed in animal reproduction studies with oral administration to pregnant rats and rabbits at doses of up to 10 and 4 times, respectively, the 12 mg/day recommended dose; postnatal development was delayed in rats at a dose of 8 times the 12 mg/day recommended dose

              Lactation

              Present in human milk; there is no information on effects on breastfed infant or effects on milk production

              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.

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              Pharmacology

              Mechanism of Action

              Hypertension: Blocks postsynaptic alpha1 receptors; alpha blockade causes arterial, arteriolar, and venous dilation; decreases total peripheral resistance and blood pressure

              Benign prostatic hyperplasia (BPH): Blocks alpha1 receptors in prostatic stromal and bladder tissues; reduces sympathetic tone-induced urethral stricture responsible for BPH symptoms

              Absorption

              Bioavailability: Immediate release, 65%; extended release, 54-59%

              Onset (antihypertensive response): Peak, 4-8 hr

              Onset (BPH response): Initial, 2 wk; peak, 4-6 weeks

              Duration: 24 hr

              Peak plasma time: 2-3 hr

              Distribution

              Protein bound: 99%

              Vd: 1-3.4 L/kg

              Metabolism

              Metabolized extensively in liver

              Metabolites: 6- and 7-O-demethyl metabolites, 6'- and 7'-hydroxy metabolites, other minor metabolites (activity unknown)

              Elimination

              Half-life: Immediate release, 22 hr; extended release, 15-19 hr

              Dialyzable: HD, no

              Total body clearance: 83-140 mL/min

              Excretion: Feces (65%), urine (0.6-9%)

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              Images

              BRAND FORM. UNIT PRICE PILL IMAGE
              Cardura oral
              -
              1 mg tablet
              Cardura oral
              -
              4 mg tablet
              Cardura oral
              -
              8 mg tablet
              Cardura oral
              -
              2 mg tablet
              doxazosin oral
              -
              2 mg tablet
              doxazosin oral
              -
              8 mg tablet
              doxazosin oral
              -
              4 mg tablet
              doxazosin oral
              -
              8 mg tablet
              doxazosin oral
              -
              2 mg tablet
              doxazosin oral
              -
              4 mg tablet
              doxazosin oral
              -
              8 mg tablet
              doxazosin oral
              -
              1 mg tablet
              doxazosin oral
              -
              4 mg tablet
              doxazosin oral
              -
              2 mg tablet
              doxazosin oral
              -
              8 mg tablet
              doxazosin oral
              -
              1 mg tablet
              doxazosin oral
              -
              1 mg tablet
              doxazosin oral
              -
              2 mg tablet
              doxazosin oral
              -
              4 mg tablet
              doxazosin oral
              -
              2 mg tablet
              doxazosin oral
              -
              1 mg tablet
              doxazosin oral
              -
              2 mg tablet
              doxazosin oral
              -
              4 mg tablet
              doxazosin oral
              -
              1 mg tablet
              doxazosin oral
              -
              4 mg tablet
              doxazosin oral
              -
              1 mg tablet
              doxazosin oral
              -
              2 mg tablet
              doxazosin oral
              -
              4 mg tablet
              doxazosin oral
              -
              1 mg tablet
              doxazosin oral
              -
              8 mg tablet
              doxazosin oral
              -
              8 mg tablet
              doxazosin oral
              -
              8 mg tablet
              doxazosin oral
              -
              4 mg tablet
              Cardura XL oral
              -
              8 mg tablet
              Cardura XL oral
              -
              4 mg tablet

              Copyright © 2010 First DataBank, Inc.

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              Patient Handout

              Patient Education
              doxazosin oral

              DOXAZOSIN EXTENDED-RELEASE TABLET - ORAL

              (dox-AZE-oh-sin)

              COMMON BRAND NAME(S): Cardura XL

              USES: Doxazosin is used in men to treat the symptoms of an enlarged prostate (benign prostatic hyperplasia-BPH). It does not shrink the prostate, but it works by relaxing the muscles in the prostate and part of the bladder. This helps to relieve symptoms of BPH such as difficulty in beginning the flow of urine, weak stream, and the need to urinate often or urgently (including during the middle of the night).Doxazosin belongs to a class of drugs known as alpha blockers.This medication should not be used to treat high blood pressure.

              HOW TO USE: Read the Patient Information Leaflet if available from your pharmacist before you start taking doxazosin and each time you get a refill. If you have any questions, ask your doctor or pharmacist.Take this medication by mouth as directed by your doctor, usually once daily with breakfast.Doxazosin may cause a sudden drop in your blood pressure, which could lead to dizziness or fainting, usually within a few hours after you take it. This risk is higher when you first start taking this drug, after your doctor increases your dose, or if you restart treatment after you stop taking it. During these times, avoid situations where you may be injured if you faint.Swallow the tablets whole. Do not crush or chew the tablets. Doing so can release all of the drug at once, increasing the risk of side effects.The dosage is based on your medical condition and response to treatment.Take this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day. If you miss taking doxazosin for a few days, you may need to restart treatment at a lower dose and gradually increase your dose again. Consult your doctor for more details.If you are switching from another form of doxazosin to this extended-release form, be sure to follow your doctor's instructions closely.Tell your doctor if your condition does not improve or if it worsens.

              SIDE EFFECTS: Dizziness, lightheadedness, or drowsiness may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.An empty tablet shell may appear in your stool. This effect is harmless because your body has already absorbed the medication.Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.Tell your doctor right away if you have any serious side effects, including: signs of infection (such as sore throat that doesn't go away, fever), fainting, shortness of breath, weakness.Get medical help right away if you have any very serious side effects, including: chest pain.Rarely, males may have a painful or prolonged erection lasting 4 or more hours. If this occurs, stop using this drug and get medical help right away, or permanent problems could occur.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

              PRECAUTIONS: Before taking doxazosin, tell your doctor or pharmacist if you are allergic to it; or to other alpha blockers such as prazosin or terazosin; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: stomach/intestine problems (such as short bowel syndrome, chronic constipation, narrow gut, slow gut movement), heart disease (such as heart failure, angina, heart attack in last 6 months), liver disease, low blood pressure, certain eye problems (cataracts, glaucoma).This drug may make you dizzy or drowsy. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis). See also How to Use section.Before having surgery (including cataract/glaucoma eye surgery), tell your doctor or dentist if you are taking or have ever taken this medication, and about all the other products you use (including prescription drugs, nonprescription drugs, and herbal products).Older adults may be more sensitive to the side effects of this drug, especially dizziness and low blood pressure when getting up from a sitting or lying position. These side effects can increase the risk of falling.During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.This medication passes into breast milk. Consult your doctor before breast-feeding.

              DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.Some products that may interact with this drug include: other alpha blocker drugs (such as prazosin, tamsulosin).If you are also taking a drug to treat erectile dysfunction-ED or pulmonary hypertension (such as sildenafil, tadalafil), your blood pressure may get too low which can lead to dizziness or fainting. Your doctor may need to adjust your medications to minimize this risk.Other medications can affect the removal of doxazosin from your body, which may affect how doxazosin works. Examples include azole antifungals (such as itraconazole, ketoconazole), macrolide antibiotics (such as clarithromycin), HIV protease inhibitors (such as lopinavir), ritonavir, among others.

              OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe dizziness, fainting.

              NOTES: Do not share this medication with others.Lab and/or medical tests (such as prostate exams, blood pressure) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.

              MISSED DOSE: If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up. See also How to Use section.

              STORAGE: Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

              Information last revised September 2023. Copyright(c) 2023 First Databank, Inc.

              IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.

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