Dosing & Uses
Dosage Forms & Strengths
tablet
- 2mg
- 4mg
capsule
- 2mg
- 4mg
- 6mg
Muscle Spasticity
Spasticity associated with multiple sclerosis and spinal cord injury
Initial: 2 mg PO q6-8hr PRN; no more than 3 doses q24hr
Maintenance: Titrate in 2-4 mg/day increments to optimum effect with minimum 1-4 days between dose increments
Not to exceed 36 mg/day; single doses >16 mg not studied
To discontinue taper gradually; decrease by 2-4 mg daily
Dosing Modifications
Renal impairment
- CrCl <25 mL/min: Use caution; clearance reduced >50%
- CrCl >25 mL/min: Not studied; use caution
Hepatic impairment
- Close monitoring of ADRs (eg, hypotension); avoid in severe impairment
Not recommended
Interactions
Interaction Checker
No Results
Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor
Contraindicated (0)
Serious - Use Alternative (36)
- abametapir
abametapir will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug. For 2 weeks after abametapir application, avoid taking drugs that are CYP1A2 substrates. If not feasible, avoid use of abametapir.
- amobarbital
amobarbital will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- armodafinil
armodafinil will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- butabarbital
butabarbital will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- butalbital
butalbital will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- carbamazepine
carbamazepine will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- cigarette smoking
cigarette smoking will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- cimetidine
cimetidine will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- ciprofloxacin
ciprofloxacin will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug. Coadministration of ciprofloxacin and tizanidine is contraindicated.
- erythromycin base
erythromycin base will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- erythromycin ethylsuccinate
erythromycin ethylsuccinate will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- erythromycin lactobionate
erythromycin lactobionate will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- erythromycin stearate
erythromycin stearate will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- fluvoxamine
fluvoxamine will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- givosiran
givosiran will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP1A2 substrates with givosiran. If unavoidable, decrease the CYP1A2 substrate dosage in accordance with approved product labeling.
- iobenguane I 131
tizanidine will decrease the level or effect of iobenguane I 131 by Other (see comment). Avoid or Use Alternate Drug. Based on the mechanism of action of iobenguane, drugs that reduce catecholamine uptake or that deplete catecholamine stores may interfere with iobenguane uptake into cells, and thus, reduce iobenguane efficacy. Discontinue interfering drugs for at least 5 half-lives before administration of either the dosimetry or an iobenguane dose. Do not administer these drugs until at least 7 days after each iobenguane dose.
- isoniazid
isoniazid will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- mefloquine
mefloquine increases toxicity of tizanidine by QTc interval. Avoid or Use Alternate Drug. Mefloquine may enhance the QTc prolonging effect of high risk QTc prolonging agents.
- metoclopramide intranasal
tizanidine, 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.
- mexiletine
mexiletine will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Contraindicated.
- modafinil
modafinil will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- olopatadine intranasal
tizanidine 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.
- pefloxacin
pefloxacin will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- peginterferon alfa 2a
peginterferon alfa 2a will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- pentobarbital
pentobarbital will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- phenobarbital
phenobarbital will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- pipemidic acid
pipemidic acid will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Contraindicated.
- ponesimod
ponesimod, tizanidine. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Consult cardiologist if considering treatment. Coadministration of ponesimod with drugs that decrease HR may have additive effects on decreasing HR and should generally not be initiated in these patients.
- primidone
primidone will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- rifampin
rifampin will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Contraindicated.
- ropeginterferon alfa 2b
ropeginterferon alfa 2b and tizanidine 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.
- secobarbital
secobarbital will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- smoking
smoking will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- tobacco use
tobacco use will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- verapamil
verapamil will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
- zileuton
zileuton will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.
Monitor Closely (39)
- acrivastine
acrivastine and tizanidine both increase sedation. Use Caution/Monitor.
- amifostine
amifostine, tizanidine. 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.
- amisulpride
amisulpride and tizanidine both increase sedation. Use Caution/Monitor.
- asenapine
asenapine and tizanidine both increase sedation. Use Caution/Monitor.
- asenapine transdermal
asenapine transdermal and tizanidine both increase sedation. Use Caution/Monitor.
- brexanolone
brexanolone, tizanidine. Either increases toxicity of the other by sedation. Use Caution/Monitor.
- candesartan
tizanidine increases effects of candesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.
- cannabidiol
cannabidiol, tizanidine. affecting hepatic enzyme CYP1A2 metabolism. Modify Therapy/Monitor Closely. Owing to the potential for both CYP1A2 induction and inhibition with the coadministration of CYP1A2 substrates and cannabidiol, consider reducing dosage adjustment of CYP1A2 substrates as clinically appropriate.
- cenobamate
cenobamate, tizanidine. Either increases effects of the other by sedation. Use Caution/Monitor.
- citalopram
citalopram will increase the level or effect of tizanidine by Other (see comment). Use Caution/Monitor. Monitor for increased psychomotor impairment and adverse effects.
- clobazam
tizanidine, clobazam. Other (see comment). Use Caution/Monitor. Comment: Concomitant administration can increase the potential for CNS effects (e.g., increased sedation or respiratory depression).
- daridorexant
tizanidine 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.
- deferasirox
deferasirox will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
- difelikefalin
difelikefalin and tizanidine both increase sedation. Use Caution/Monitor.
- eprosartan
tizanidine increases effects of eprosartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.
- escitalopram
tizanidine increases toxicity of escitalopram by pharmacodynamic synergism. Use Caution/Monitor. CNS depressants may enhance the psychomotor impairment of escitalopram.
- esketamine intranasal
esketamine intranasal, tizanidine. Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely.
- ethinylestradiol
ethinylestradiol will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. Monitor for tizanidine adverse effects (eg, hypotension or bradycardia)
- fexinidazole
fexinidazole will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
- ganaxolone
tizanidine and ganaxolone both increase sedation. Use Caution/Monitor.
- irbesartan
tizanidine increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.
- lasmiditan
lasmiditan, tizanidine. Either increases effects of the other by sedation. Use Caution/Monitor. Coadministration of lasmiditan and other CNS depressant drugs, including alcohol have not been evaluated in clinical studies. Lasmiditan may cause sedation, as well as other cognitive and/or neuropsychiatric adverse reactions.
- lemborexant
lemborexant will increase the level or effect of tizanidine by sedation. Modify Therapy/Monitor Closely. Dosage adjustment may be necessary if lemborexant is coadministered with other CNS depressants because of potentially additive effects.
- levonorgestrel oral/ethinylestradiol/ferrous bisglycinate
levonorgestrel oral/ethinylestradiol/ferrous bisglycinate will increase the level or effect of tizanidine by decreasing metabolism. Use Caution/Monitor. Combined oral contraceptives containing EE may inhibit the metabolism and increase plasma concentrations of cyclosporine.
- losartan
tizanidine increases effects of losartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.
- lurasidone
lurasidone, tizanidine. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Potential for increased CNS depressant effects when used concurrently; monitor for increased adverse effects and toxicity.
- maraviroc
maraviroc, tizanidine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of orthostatic hypotension.
- midazolam intranasal
midazolam intranasal, tizanidine. 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.
- nitroglycerin rectal
nitroglycerin rectal, tizanidine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Observe for possible additive hypotensive effects during concomitant use. .
- obeticholic acid
obeticholic acid will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Modify Therapy/Monitor Closely. CYP1A2 substrates that have a narrow therapeutic index should be monitored closely and the dose adjusted accordingly.
- olmesartan
tizanidine increases effects of olmesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.
- osilodrostat
osilodrostat will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
- rucaparib
rucaparib will increase the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP1A2 substrates, if clinically indicated.
- sacubitril/valsartan
tizanidine increases effects of sacubitril/valsartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.
- stiripentol
stiripentol, tizanidine. affecting hepatic enzyme CYP1A2 metabolism. Modify Therapy/Monitor Closely. Stiripentol is a CYP1A2 inhibitor and inducer. Monitor CYP1A2 substrates coadministered with stiripentol for increased or decreased effects. CYP1A2 substrates may require dosage adjustment.
stiripentol, tizanidine. Either increases effects of the other by sedation. Use Caution/Monitor. Concomitant use stiripentol with other CNS depressants, including alcohol, may increase the risk of sedation and somnolence. - telmisartan
tizanidine increases effects of telmisartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.
- teriflunomide
teriflunomide decreases levels of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.
- valsartan
tizanidine increases effects of valsartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.
- vemurafenib
vemurafenib increases levels of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. Concomitant use of vemurafenib with agents with narrow therapeutic windows is not recommended as vemurafenib may alter their concentrations. If coadministration cannot be avoided, use caution and consider dose reduction of concomitant CYP1A2 substrate drug.
Minor (79)
- acebutolol
tizanidine increases effects of acebutolol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- alfuzosin
tizanidine increases effects of alfuzosin by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- amiloride
tizanidine increases effects of amiloride by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- amlodipine
tizanidine increases effects of amlodipine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- asenapine
tizanidine increases effects of asenapine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- atenolol
tizanidine increases effects of atenolol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- benazepril
tizanidine increases effects of benazepril by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- bendroflumethiazide
tizanidine increases effects of bendroflumethiazide by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- betaxolol
tizanidine increases effects of betaxolol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- bisoprolol
tizanidine increases effects of bisoprolol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- bosentan
tizanidine increases effects of bosentan by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- bumetanide
tizanidine increases effects of bumetanide by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- captopril
tizanidine increases effects of captopril by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- carvedilol
tizanidine increases effects of carvedilol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- celiprolol
tizanidine increases effects of celiprolol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- chlorothiazide
tizanidine increases effects of chlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- chlorthalidone
tizanidine increases effects of chlorthalidone by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- clevidipine
tizanidine increases effects of clevidipine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- clonidine
tizanidine increases effects of clonidine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- cyclopenthiazide
tizanidine increases effects of cyclopenthiazide by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- diltiazem
tizanidine increases effects of diltiazem by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- doxazosin
tizanidine increases effects of doxazosin by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- drospirenone
tizanidine increases effects of drospirenone by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- enalapril
tizanidine increases effects of enalapril by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- eplerenone
tizanidine increases effects of eplerenone by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- epoprostenol
tizanidine increases effects of epoprostenol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- esmolol
tizanidine increases effects of esmolol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- ethacrynic acid
tizanidine increases effects of ethacrynic acid by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- ethinylestradiol
ethinylestradiol increases levels of tizanidine by unspecified interaction mechanism. Minor/Significance Unknown.
- felodipine
tizanidine increases effects of felodipine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- fenoldopam
tizanidine increases effects of fenoldopam by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- fosinopril
tizanidine increases effects of fosinopril by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- furosemide
tizanidine increases effects of furosemide by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- guanfacine
tizanidine increases effects of guanfacine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- hydralazine
tizanidine increases effects of hydralazine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- hydrochlorothiazide
tizanidine increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- iloprost
tizanidine increases effects of iloprost by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- imidapril
tizanidine increases effects of imidapril by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- indapamide
tizanidine increases effects of indapamide by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- isradipine
tizanidine increases effects of isradipine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- ketanserin
tizanidine increases effects of ketanserin by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- labetalol
tizanidine increases effects of labetalol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- lisinopril
tizanidine increases effects of lisinopril by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- mecamylamine
tizanidine increases effects of mecamylamine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- mestranol
mestranol increases levels of tizanidine by unspecified interaction mechanism. Minor/Significance Unknown.
- methyclothiazide
tizanidine increases effects of methyclothiazide by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- metolazone
tizanidine increases effects of metolazone by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- metoprolol
tizanidine increases effects of metoprolol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- metyrosine
tizanidine increases effects of metyrosine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- minoxidil
tizanidine increases effects of minoxidil by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- moexipril
tizanidine increases effects of moexipril by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- moxisylyte
tizanidine increases effects of moxisylyte by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- moxonidine
tizanidine increases effects of moxonidine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- nadolol
tizanidine increases effects of nadolol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- nebivolol
tizanidine increases effects of nebivolol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- nicardipine
tizanidine increases effects of nicardipine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- nifedipine
tizanidine increases effects of nifedipine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- nisoldipine
tizanidine increases effects of nisoldipine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- omeprazole
omeprazole will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.
- penbutolol
tizanidine increases effects of penbutolol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- perindopril
tizanidine increases effects of perindopril by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- phenoxybenzamine
tizanidine increases effects of phenoxybenzamine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- phentolamine
tizanidine increases effects of phentolamine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- pindolol
tizanidine increases effects of pindolol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- prazosin
tizanidine increases effects of prazosin by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- propranolol
tizanidine increases effects of propranolol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- quinapril
tizanidine increases effects of quinapril by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- ramipril
tizanidine increases effects of ramipril by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- silodosin
tizanidine increases effects of silodosin by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- sotalol
tizanidine increases effects of sotalol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- spironolactone
tizanidine increases effects of spironolactone by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- terazosin
tizanidine increases effects of terazosin by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- timolol
tizanidine increases effects of timolol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- torsemide
tizanidine increases effects of torsemide by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- trandolapril
tizanidine increases effects of trandolapril by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- treprostinil
tizanidine increases effects of treprostinil by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- triamterene
tizanidine increases effects of triamterene by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- verapamil
tizanidine increases effects of verapamil by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
- zotepine
tizanidine increases effects of zotepine by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.
Adverse Effects
>10%
Dry mouth (46-50%)
Somnolence (46-50%)
Dizziness (16-20%)
Asthenia (10-45%)
1-10%
Blurred vision (3%)
Constipation (4%)
Infection (6%)
LFT abnormalities (3-5%)
Speech disorder (3%)
Vomiting (3%)
Urinary frequency (3%)
UTI (10%)
Frequency Not Defined
Asthenia
Bradycardia
Hypotension
Orthostatic hypotension
Syncope (rare)
Warnings
Contraindications
Hypersensitivity
Concomitant ciprofloxacin or fluvoxamine, or other potent CYP1A2 inhibitors
Cautions
Potential for hypotension
Caution in renal/hepatic impairment
Women on oral contraceptives
Hepatotoxicity may occur; monitor aminotransferases prior to and during use
Sedation may occur (dose related); may potentiate effect of sedative drugs or ethanol
Visual hallucinations may occur
CYP1A2 inducers may decrease levels
Rebound hypertension, tachycardia, and hypertonia reported upon abrupt discontinuation; decrease doses slowly in patients taking concomitant narcotics or high doses (20-28 mg/day) for prolonged periods
Pregnancy & Lactation
Pregnancy
There are no adequate data on developmental risk associated with use in pregnant women
Reproductive potential
- There are no adequate and well-controlled studies in humans on effect of drug on female or male reproductive potential; oral administration of to male and female rats resulted in adverse effects on fertility
Animal data
- In animal studies, administration of drug during pregnancy resulted in developmental toxicity (embryofetal and postnatal offspring mortality and growth deficits) at doses less than those used clinically, which were not associated with maternal toxicity
Lactation
There are no data on presence of drug in human milk, effects on breastfed infant, or on human milk production; animal studies have reported the presence of drug in milk of lactating animals
The developmental and health benefits of breastfeeding should be considered along with mother’s clinical need for drug and any potential adverse effects on breastfed infant from drug 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.Pharmacology
Mechanism of Action
Alpha-2 adrenergic receptor agonist structurally related to clonidine; increases presynaptic inhibition of motor neurons
Absorption
Bioavailability: 40%
Peak serum time: 1-4 hr
Distribution
Protein bound: 30%
Vd: 2.4 L/kg
Metabolism
Extensively metabolized in the liver
Elimination
Half-life: 2.5 hr
Excretion: Feces (20%); urine (60%)
Images
| BRAND | FORM. | UNIT PRICE | PILL IMAGE |
|---|---|---|---|
| Zanaflex oral - | 6 mg capsule |  | |
| Zanaflex oral - | 4 mg capsule |  | |
| Zanaflex oral - | 2 mg capsule |  | |
| Zanaflex oral - | 4 mg tablet |  | |
| tizanidine oral - | 2 mg tablet |  | |
| tizanidine oral - | 2 mg tablet |  | |
| tizanidine oral - | 4 mg tablet |  | |
| tizanidine oral - | 4 mg tablet |  | |
| tizanidine oral - | 2 mg tablet |  | |
| tizanidine oral - | 4 mg tablet |  | |
| tizanidine oral - | 4 mg tablet |  | |
| tizanidine oral - | 4 mg tablet |  | |
| tizanidine oral - | 6 mg capsule | | |
| tizanidine oral - | 2 mg capsule | | |
| tizanidine oral - | 4 mg tablet |  | |
| tizanidine oral - | 2 mg capsule |  | |
| tizanidine oral - | 2 mg capsule |  | |
| tizanidine oral - | 2 mg tablet |  | |
| tizanidine oral - | 4 mg capsule | | |
| tizanidine oral - | 2 mg tablet |  | |
| tizanidine oral - | 6 mg capsule |  | |
| tizanidine oral - | 4 mg capsule |  | |
| tizanidine oral - | 6 mg capsule |  | |
| tizanidine oral - | 4 mg capsule |  | |
| tizanidine oral - | 2 mg capsule |  | |
| tizanidine oral - | 2 mg capsule |  | |
| tizanidine oral - | 6 mg capsule |  | |
| tizanidine oral - | 4 mg capsule |  | |
| tizanidine oral - | 4 mg tablet |  | |
| tizanidine oral - | 2 mg capsule |  | |
| tizanidine oral - | 2 mg tablet |  | |
| tizanidine oral - | 6 mg capsule |  | |
| tizanidine oral - | 4 mg capsule |  | |
| tizanidine oral - | 4 mg capsule |  | |
| tizanidine oral - | 2 mg tablet |  |
Copyright © 2010 First DataBank, Inc.
Patient Handout
tizanidine oral
TIZANIDINE - ORAL
(tye-ZAN-i-deen)
COMMON BRAND NAME(S): Zanaflex
USES: This medication is used to treat muscle spasms caused by certain conditions (such as multiple sclerosis, spinal cord injury). It works by helping to relax the muscles.
HOW TO USE: Take this medication by mouth as directed by your doctor, usually every 6 to 8 hours.The dosage is based on your medical condition, response to treatment, and other medications you may be taking. Be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products). To reduce your risk of side effects, your doctor may direct you to start this medication at a low dose and gradually increase your dose. Follow your doctor's instructions carefully. Do not take more than 36 milligrams a day or more than 3 doses in a 24-hour period.Your body will absorb this medication differently depending on whether you take it as a tablet or capsule, whether you take it with food or on an empty stomach, or if you sprinkle the contents of the capsule on food. Be sure to discuss with your doctor how to take this medication to determine the best way to take your dose, especially when changes to your dose are being considered or if your doctor prescribes a different form of tizanidine (such as tablet or capsule).If you suddenly stop using this medication, you may have withdrawal symptoms (such as anxiety, tremor, increased blood pressure/heart rate/muscle tenseness). To help prevent withdrawal, your doctor may lower your dose slowly. Withdrawal is more likely if you have used tizanidine for a long time or in high doses. Tell your doctor or pharmacist right away if you have withdrawal.Tell your doctor if your condition does not improve or if it worsens.
SIDE EFFECTS: Dry mouth, drowsiness, dizziness, lightheadedness, constipation, weakness, and tiredness may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.To relieve dry mouth, suck (sugarless) hard candy or ice chips, chew (sugarless) gum, drink water, or use a saliva substitute.To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.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: fainting, mental/mood changes (such as hallucinations), slow/irregular heartbeat, vision changes (such as blurred vision).Tizanidine has rarely caused very serious (rarely fatal) liver disease. Tell your doctor right away if you develop symptoms of liver disease, including: nausea/vomiting that doesn't stop, severe stomach/abdominal pain, dark urine, yellowing eyes/skin.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 tizanidine, tell your doctor or pharmacist if you are allergic to it; 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: low blood pressure, kidney disease, liver disease.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. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).Before having surgery, tell your doctor or dentist about all the 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 drowsiness. These 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.It is unknown if this drug 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: certain drugs to treat high blood pressure (alpha agonists such as clonidine, methyldopa).Other medications can affect the removal of tizanidine from your body, which may affect how tizanidine works. Examples include birth control pills, ciprofloxacin, fluvoxamine, viloxazine, among others.Tell your doctor or pharmacist if you are taking other products that cause drowsiness including alcohol, marijuana (cannabis), antihistamines (such as cetirizine, diphenhydramine), drugs for sleep or anxiety (such as alprazolam, diazepam, zolpidem), other muscle relaxants, and opioid pain relievers (such as codeine).Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely.
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/drowsiness, confusion, slow/shallow breathing, fainting.
NOTES: Do not share this medication with others.Lab and/or medical tests (such as blood pressure, liver function) 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.
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 November 2022. 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.
Formulary
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.
