Medicine guide

Tizanidine Hydrochloride

4 mg · Capsule

Prescription only
Central alpha-2 Adrenergic Agonist

Active substance: Tizanidine Hydrochloride
Used in: Heart, blood pressure and circulation
Made by: Zydus Lifesciences Limited
Source: Official label

Quoted from the official source. Not yet reviewed by Mediclarum — the leaflet in your pack is authoritative.

At a glance

Quoted from the official label · 2025-12-15

What it is

Central alpha-2 Adrenergic Agonist

Used for

Tizanidine capsules are a central alpha-2-adrenergic agonist indicated for the treatment of spasticity. ( 1 ) Tizanidine capsules are indicated for the treatment of spasticity in

The label’s usual adult dose

( 2.2 , 2.6 , 12.3 ) Patients with renal impairment (creatinine clearance <25 mL/min) or hepatic impairment:

2 mg by mouth every 6 to 8 hours, as needed, up to a maximum of 3 doses in 24 hours ( 2.2 ) Dosage can be increased by 2 mg to 4 mg per dose every 1 to 4 days; maximum total daily dosage is 36 mg ( 2.2 ) Tizanidine pharmacokinetics differs between tablets and capsules, and when taken with or without food.

Full directions ↓

Do not take it if

Concomitant use with strong CYP1A2 inhibitors ( 4 , 7.1 ) Patients with a history of hypersensitivity to tizanidine or the ingredients in tizanidine capsules ( 4 , 5.5 ) Tizanidine capsules are contraindicated in patients:

All warnings ↓

Good to know

Prescription only
FDA enforcement reports list no ongoing recall, and none from the last two years, for this product code · checked 2026-10-02

63other products contain Tizanidine Hydrochloride — compare makers, forms and strengths

Every line above is selected, not written, from the official label. Nothing is reworded. DailyMed

What it is for

Tizanidine capsules are a central alpha-2-adrenergic agonist indicated for the treatment of spasticity. ( 1 ) Tizanidine capsules are indicated for the treatment of spasticity in
adults.

From the official label · 2025-12-15 · DailyMed

How it works

From this product’s own US prescribing label.

Tizanidine is a central alpha-2-adrenergic receptor agonist and presumably reduces spasticity by increasing presynaptic inhibition of motor neurons.
The effects of tizanidine are greatest on polysynaptic pathways.

Half-life2.5 h

Mostly cleared after≈ 12.5 hfive half-lives — our arithmetic

How the body breaks it down

Approximately 95% of an administered dose is metabolized.

With food

Zanaflex capsules and tizanidine tablets are bioequivalent to each other under fasting conditions, but not under fed conditions (see Absorption, Effect of Food).

Quoted from the prescribing label, sections “Mechanism of Action” and “Pharmacokinetics”. DailyMed · 2025-12-15

Do not take it if

Concomitant use with strong CYP1A2 inhibitors ( 4 , 7.1 ) Patients with a history of hypersensitivity to tizanidine or the ingredients in tizanidine capsules ( 4 , 5.5 ) Tizanidine capsules are contraindicated in patients:
taking strong CYP1A2inhibitors [see Drug Interactions (7.1) ] . with a history of hypersensitivity to tizanidine or the ingredients in tizanidine capsules.
Symptoms have included anaphylaxis and angioedema [see Warnings and Precautions (5.5) ].

Quoted from the official label, section “Contraindications”.

How to take it

These directions are for this exact strength and form. Another one is different.

Monitoring of aminotransferase levels is recommended at baseline and 1 month after maximum dose is achieved.
( 2.1 ) Recommended starting dose:
2 mg by mouth every 6 to 8 hours, as needed, up to a maximum of 3 doses in 24 hours ( 2.2 ) Dosage can be increased by 2 mg to 4 mg per dose every 1 to 4 days; maximum total daily dosage is 36 mg ( 2.2 ) Tizanidine pharmacokinetics differs between tablets and capsules, and when taken with or without food.
These differences could result in a change in tolerability and control of symptoms.
Consistent administration with respect to food is recommended.
If substitution between dosage forms is necessary, take into consideration these pharmacokinetic differences.
( 2.2 , 2.6 , 12.3 ) Patients with renal impairment (creatinine clearance <25 mL/min) or hepatic impairment:
use lower individual doses during titration.
If higher doses are required, individual doses rather than dosing frequency should be increased.
( 2.3 , 2.4 ) To discontinue tizanidine hydrochloride, decrease dose slowly to minimize the risk of withdrawal adverse reactions ( 2.5 )
2.1 Recommended Evaluation and Testing Before and After Initiating Tizanidine Capsules Monitoring of aminotransferase levels is recommended at baseline and 1 month after maximum dose is achieved [see Warnings and Precautions (5.2) ].
2.2 Recommended Dosage The recommended starting dose is 2 mg by mouth every 6 to 8 hours, as needed, to a maximum of three doses in 24 hours.
Dosage can be gradually increased every 1 to 4 days by 2 mg to 4 mg at each dose based on clinical response and tolerability.
The maximum total daily dosage is 36 mg.
Single doses greater than 16 mg have not been studied.
There are pharmacokinetic differences when administering tizanidine hydrochloride between the fed or fasted state [see Clinical Pharmacology (12.3) ].
Tizanidine capsules may be taken with or without food; however, consistent administration with respect to food is recommended to reduce variability in tizanidine plasma exposure .
Because of the short duration of therapeutic effect, treatment with tizanidine hydrochloride should be reserved for those daily activities and times when relief of spasticity is most important.
2.3 Recommended Dosage in Patients with Renal Impairment In patients with creatinine clearance <25 mL/min, use lower individual doses during titration.
If higher doses are required, the individual doses rather than dosing frequency should be increased [see Use in Specific Populations (8.6) and Clinical Pharmacology (12.3) ] .
2.4 Recommended Dosage in Patients with Hepatic Impairment In patients with hepatic impairment, use lower individual doses during titration.
If higher doses are required, individual doses rather than dosing frequency should be increased [see Use in Specific Populations (8.7) and Clinical Pharmacology (12.3) ].
2.5 Discontinuation of Tizanidine Capsules When discontinuing tizanidine capsules, particularly in patients who have been receiving high doses for long periods or who may be on concomitant treatment with narcotics, decrease the dosage by 2 mg to 4 mg per day to minimize the risk of withdrawal adverse reactions [see Drug Abuse and Dependence (9.3) ].
2.6 Switching Between with/without Food and Different Tizanidine Dosage There are pharmacokinetic differences when:
1) switching between administration of tizanidine capsules with or without food 2) switching between dosage forms if being administered with food .
If these situations occur, monitor patients for therapeutic effect or adverse reactions [see Dosage and Administration (2.2) and Clinical Pharmacology (12.3)

Quoted from the official label, section “Dosage & Administration”.

Other warnings

Hypotension:
monitor for signs and symptoms of hypotension, in particular in patients receiving concurrent antihypertensives; tizanidine should not be used with other α 2 -adrenergic agonists ( 5.1 , 7.5 ) Risk of liver injury:
monitor ALTs; discontinue tizanidine if liver injury occurs ( 5.2 ) Sedation:
Tizanidine may interfere with everyday activities; sedative effects of tizanidine, alcohol, and other central nervous system (CNS) depressants are additive ( 5.3 , 7.4 ) Hallucinations:
consider discontinuation of tizanidine ( 5.4 )
5.1 Hypotension Tizanidine is an α 2 -adrenergic agonist that can produce hypotension [see Adverse Reactions (6.1) and Drug Interactions (7.5) ] .
Syncope has been reported in patients treated with tizanidine in the postmarketing setting.
The risk of hypotension may be minimized by dose titration; monitoring for signs and symptoms of hypotension prior to dosage increase may minimize the risks associated with hypotension.
In addition, patients moving from a supine to fixed upright position may be at increased risk for hypotension and orthostatic effects.
Monitor for hypotension when tizanidine is used in patients receiving concurrent antihypertensive therapy.
It is not recommended that tizanidine be used with other α 2 -adrenergic agonists.
Clinically significant hypotension (decreases in both systolic and diastolic pressure) has been reported with concomitant administration of tizanidine and strong CYP1A2 inhibitors [see Clinical Pharmacology (12.3) ].
Therefore, concomitant use of tizanidine with strong CYP1A2 inhibitors is contraindicated [see Contraindications (4 ) and Drug Interactions (7.1) ] .
5.2 Liver Injury Tizanidine may cause hepatocellular liver injury.
Liver function test abnormality and hepatotoxicity have been observed with tizanidine [see Adverse Reactions ( 6.1 , 6.2 )].
Monitoring of aminotransferase levels is recommended at baseline and 1 month after maximum dose is achieved, or if hepatic injury is suspected [see Dosage and Administration (2.1) and Use in Specific Populations (8.7) ].
5.3 Sedation Tizanidine can cause sedation, which may interfere with everyday activity.
In the multiple dose studies of tizanidine, the prevalence of patients with sedation peaked following the first week of titration and then remained stable for the duration of the maintenance phase of the study [see Adverse Reactions (6.1) ] .
The CNS depressant effects of tizanidine with alcohol and other CNS depressants (e.g., benzodiazepines, opioids, tricyclic antidepressants) may be additive [see Drug Interactions (7.4) ] .
5.4 Hallucinosis/Psychotic-Like Symptoms Tizanidine use has been associated with hallucinations.
Formed, visual hallucinations or delusions were reported in 5 of 170 patients (3%) in two North American controlled clinical studies.
Most of the patients were aware that the events were unreal.
One patient developed psychosis in association with the hallucinations.
One patient among these 5 continued to have problems for at least 2 weeks following discontinuation of tizanidine.
Hallucinations have also been reported with tizanidine use in the postmarketing setting.
Consider discontinuing tizanidine in patients who develop hallucinations.
5.5 Hypersensitivity Reactions Tizanidine can cause anaphylaxis.
Signs and symptoms of hypersensitivity, including respiratory compromise, urticaria, and angioedema of the throat and tongue, have been reported.
Tizanidine is contraindicated in patients with a history of hypersensitivity reactions to tizanidine [see Contraindications (4) ].
5.6 Withdrawal Adverse Reactions Tizanidine can cause withdrawal adverse reactions, which include rebound hypertension, tachycardia, and hypertonia.
To minimize the risk of these reactions, particularly in patients who have been receiving high doses of tizanidine (20 mg to 28 mg daily) for long periods of time (9 weeks or more) or who may be on concomitant treatment with narcotics, the tizanidine dosage should be decreased slowly [see Dosage and Administration (2.5) ] .

Quoted from the official label, section “Warnings”.

Pregnancy and breastfeeding

Risk Summary There are no adequate data on the developmental risk associated with use of tizanidine in pregnant women.
In animal studies, administration of tizanidine 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 (see Animal Data ).
In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.
The background risk of major birth defects and miscarriage for the indicated population is unknown.
Data Animal Data Oral administration of tizanidine (0.3 mg/kg/day to 100 mg/kg/day) to pregnant rats during the period of organogenesis resulted in embryofetal and postnatal offspring mortality and reductions in body weight at doses of 30 mg/kg/day and above.
Maternal toxicity was observed at the highest dose tested.
The no-effect dose for embryofetal developmental toxicity in rats (3 mg/kg/day) is similar to the maximum recommended human dose (MRHD) of 36 mg/day on a body surface area (mg/m 2 ) basis.
Oral administration of tizanidine (1 mg/kg/day to 100 mg/kg/day) to pregnant rabbits during the period of organogenesis resulted in embryofetal and postnatal offspring mortality at all doses.
Maternal toxicity was observed at the highest dose tested.
Oral administration of tizanidine (10 mg/kg/day and 30 mg/kg/day) during the perinatal period of pregnancy (2 to 6 days prior to delivery) resulted in increased postnatal offspring mortality at both doses.
A no-effect dose for embryofetal developmental toxicity in rabbit was not identified.
The lowest dose tested (1 mg/kg/day) is less than the MRHD on a mg/m 2 basis.
In a pre- and postnatal development study in rats, oral administration of tizanidine (3mg/kg/day to 30 mg/kg/day) resulted in increased postnatal offspring mortality.
A no-effect dose for pre- and postnatal developmental toxicity was not identified.
The lowest dose tested (3 mg/kg/day) is similar to the MRHD on a mg/m 2 basis, respectively.
8.3 Females and Males of Reproductive Potential There are no adequate and well-controlled studies in humans on the effect of tizanidine on female or male reproductive potential.
Oral administration of tizanidine to male and female rats resulted in adverse effects on fertility [see Nonclinical Toxicology (13.1) ].
IN SPECIFIC POPULATIONS Pregnancy:
Based on animal data, may cause fetal harm ( 8.1 ) Geriatric use:
Tizanidine should be used with caution in elderly patients because clearance is decreased four-fold ( 8.5 )
8.1 Pregnancy Risk Summary There are no adequate data on the developmental risk associated with use of tizanidine in pregnant women.
In animal studies, administration of tizanidine 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 (see Animal Data ).
In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.
The background risk of major birth defects and miscarriage for the indicated population is unknown.
Data Animal Data Oral administration of tizanidine (0.3 mg/kg/day to 100 mg/kg/day) to pregnant rats during the period of organogenesis resulted in embryofetal and postnatal offspring mortality and reductions in body weight at doses of 30 mg/kg/day and above.
Maternal toxicity was observed at the highest dose tested.
The no-effect dose for embryofetal developmental toxicity in rats (3 mg/kg/day) is similar to the maximum recommended human dose (MRHD) of 36 mg/day on a body surface area (mg/m 2 ) basis.
Oral administration of tizanidine (1 mg/kg/day to 100 mg/kg/day) to pregnant rabbits during the period of organogenesis resulted in embryofetal and postnatal offspring mortality at all doses.
Maternal toxicity was observed at the highest dose tested.
Oral administration of tizanidine (10 mg/kg/day and 30 mg/kg/day) during the perinatal period of pregnancy (2 to 6 days prior to delivery) resulted in increased postnatal offspring mortality at both doses.
A no-effect dose for embryofetal developmental toxicity in rabbit was not identified.
The lowest dose tested (1 mg/kg/day) is less than the MRHD on a mg/m 2 basis.
In a pre- and postnatal development study in rats, oral administration of tizanidine (3mg/kg/day to 30 mg/kg/day) resulted in increased postnatal offspring mortality.
A no-effect dose for pre- and postnatal developmental toxicity was not identified.
The lowest dose tested (3 mg/kg/day) is similar to the MRHD on a mg/m 2 basis, respectively.
8.2 Lactation Risk Summary There are no data on the presence of tizanidine in human milk, the effects on the breastfed infant, or the effects on human milk production.
Animal studies have reported the presence of tizanidine in the milk of lactating animals.
The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for tizanidine and any potential adverse effects on the breastfed infant from tizanidine or from the underlying maternal condition.
8.3 Females and Males of Reproductive Potential There are no adequate and well-controlled studies in humans on the effect of tizanidine on female or male reproductive potential.
Oral administration of tizanidine to male and female rats resulted in adverse effects on fertility [see Nonclinical Toxicology (13.1) ].
8.4 Pediatric Use Safety and effectiveness in pediatric patients have not been established.
Juvenile Animal Toxicity Data Oral administration of tizanidine (0, 1, 3, and 10 mg/kg/day) to juvenile rats from postnatal day (PND) 7 through PND 70 resulted in delayed sexual maturation in males at all doses, reduced body weight gain, delayed sexual maturation in females, and bilateral corneal crystals at the mid and high doses.
Corneal crystals were still observed at the mid and high doses after a three-week recovery period.
Neurobehavioral deficits were observed on a learning and memory task at the high dose.
A no-effect dose for adverse effects on postnatal development not identified.
8.5 Geriatric Use Tizanidine is known to be substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in patients with impaired renal function.
Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.
Clinical studies of tizanidine did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently than younger subjects.
Pharmacokinetic data showed that younger subjects cleared tizanidine faster than the elderly subjects [see Clinical Pharmacology (12.3) ] .
In elderly patients with renal insufficiency (creatinine clearance <25 mL/min), tizanidine clearance is reduced compared to healthy elderly subjects; this would be expected to lead to a longer duration of clinical effect.
During titration, the individual doses should be reduced.
If higher doses are required, individual doses rather than dosing frequency should be increased.
Monitor elderly patients because they may have an increased risk for adverse reactions associated with tizanidine.
8.6 Renal Impairment In patients with renal insufficiency (creatinine clearance <25 mL/min), clearance of tizanidine was reduced [see Clinical Pharmacology (12.3) ] .
In these patients, dosage reduction is recommended [see Dosage and Administration (2.3) ] .
Because the risk of adverse reactions to tizanidine may be greater in patients with impaired renal function, monitor these patients closely for the onset or increase in severity of common adverse reactions [see Adverse Reactions (6.1) ].
8.7 Hepatic Impairment Tizanidine should be used with caution in patients with hepatic impairment.
The influence of hepatic impairment on the pharmacokinetics of tizanidine has not been evaluated.
Because tizanidine is extensively metabolized in the liver, hepatic impairment would be expected to have significant effects on pharmacokinetics of tizanidine [see Warnings and Precautions (5.2) and Clinical Pharmacology (12.3) ].
In patients with hepatic impairment, dosage reduction is recommended [see Dosage and Administration (2.4) ].

Quoted from the official label, section “OTC — Pregnancy or Breast Feeding”.

Other medicines

Moderate or weak CYP1A2 inhibitors:
avoid concomitant use; may cause hypotension, bradycardia, or excessive drowsiness; if concomitant use is necessary and adverse reactions occur, reduce tizanidine dosage or discontinue.
( 7.2 , 12.3 )
7.1 Strong CYP1A2 Inhibitors Concomitant use of tizanidine with strong cytochrome P450 1A2 (CYP1A2) inhibitors (e.g., fluvoxamine, ciprofloxacin) is contraindicated.
Changes in pharmacokinetics of tizanidine when administered with a strong CYP1A2 inhibitor resulted in significantly decreased blood pressure, increased drowsiness, and increased psychomotor impairment [see Contraindications (4) and Clinical Pharmacology (12.3) ].
7.2 Moderate or Weak CYP1A2 Inhibitors Concomitant use of tizanidine with moderate or weak CYP1A2 inhibitors (e.g., zileuton, antiarrhythmics [amiodarone, mexiletine, propafenone, and verapamil], cimetidine, famotidine, oral contraceptives, acyclovir, and ticlopidine) should be avoided.
If concomitant use is clinically necessary, and adverse reactions such as hypotension, bradycardia, or excessive drowsiness occur, reduce tizanidine dosage or discontinue tizanidine therapy [see Clinical Pharmacology (12.3) ].
7.3 Oral Contraceptives Concomitant use of tizanidine with oral contraceptives is not recommended.
However, if concomitant use is clinically necessary and adverse reactions such as hypotension, bradycardia, or excessive drowsiness occur, reduce or discontinue tizanidine therapy [see Clinical Pharmacology (12.3) ].
7.4 Alcohol and Other CNS Depressants Alcohol increases the exposure of tizanidine after administration of tizanidine.
This was associated with an increase in adverse reactions of tizanidine.
Concomitant use of tizanidine with CNS depressants (e.g., alcohol, benzodiazepines, opioids, tricyclic antidepressants) may cause additive CNS depressant effects, including sedation.
Monitor patients who take tizanidine with another CNS depressant for symptoms of excess sedation [see Clinical Pharmacology (12.3) ]. 7.5 a 2 -Adrenergic Agonists Concomitant use of tizanidine with other α 2 -adrenergic agonists is not recommended because hypotensive effects may be cumulative [ see Warnings and Precautions (5.1) ].
7.6 Antihypertensive Medications Concomitant use of tizanidine with antihypertensive medications may cause additive hypotensive effects [see Warnings and Precautions (5.1) ] .
Monitor patients who take tizanidine with antihypertensive medications for hypotension.

Quoted from the official label, section “Drug Interactions”.

If you take too much

In an emergency, call your local emergency number or a poison control centre.

A review of the safety surveillance database revealed cases of intentional and accidental tizanidine overdose.
Some of the cases resulted in fatality and many of the intentional overdoses were with multiple drugs, including CNS depressants.
The clinical manifestations of tizanidine overdose were consistent with its known pharmacology.
In the majority of cases, a decrease in sensorium was observed including lethargy, somnolence, confusion, and coma.
Depressed cardiac function is also observed including most often bradycardia and hypotension.
Respiratory depression is another common feature of tizanidine overdose.
Should overdose occur, ensure the adequacy of an airway and monitor cardiovascular and respiratory function.
Dialysis is not likely to be an efficient method of removing tizanidine from the body [see Description (11) ] .
In general, symptoms resolve within one to three days following discontinuation of tizanidine and administration of appropriate therapy.
Because of the similar mechanism of action, symptoms and management of tizanidine overdose are similar to that following clonidine overdose.
For the most recent information concerning the management of overdose, contact a poison control center.

Quoted from the official label, section “Overdosage”.

Misuse and dependence

9.1 Controlled Substance Tizanidine capsules contains tizanidine, which is not a controlled substance.
9.2 Abuse Abuse is the intentional, non-therapeutic use of a drug, even once, for its desirable psychological or physiological effects.
Abuse potential was not evaluated in human studies.
Rats were able to distinguish tizanidine from saline in a standard discrimination paradigm, after training, but failed to generalize the effects of morphine, cocaine, diazepam, or phenobarbital to tizanidine.
9.3 Dependence Physical dependence is a state that develops as a result of physiological adaptation in response to repeated drug use, manifested by withdrawal signs and symptoms after abrupt discontinuation or a significant dose reduction of a drug.
Tizanidine is closely related to clonidine, which is often abused in combination with narcotics and is known to cause symptoms of rebound upon abrupt withdrawal.
Cases of rebound symptoms on sudden withdrawal of tizanidine have been reported.
The case reports suggest that these patients were also misusing narcotics.
Withdrawal symptoms included hypertension, tachycardia, hypertonia, tremor, and anxiety.
Withdrawal symptoms are more likely to occur in cases where high doses are used, especially for prolonged periods, or with concomitant use of narcotics.
If therapy needs to be discontinued, the dose should be decreased slowly to minimize the risk of withdrawal symptoms [see Dosage and Administration (2.5) ].
Monkeys were shown to self-administer tizanidine in a dose-dependent manner, and abrupt cessation of tizanidine produced transient signs of withdrawal at doses >35 times the maximum recommended human dose on a mg/m 2 basis.
These transient withdrawal signs (increased locomotion, body twitching, and aversive behavior toward the observer) were not reversed by naloxone administration.

Quoted from the official label, section “Drug Abuse and Dependence”.

Use in children

Safety and effectiveness in pediatric patients have not been established.
Juvenile Animal Toxicity Data Oral administration of tizanidine (0, 1, 3, and 10 mg/kg/day) to juvenile rats from postnatal day (PND) 7 through PND 70 resulted in delayed sexual maturation in males at all doses, reduced body weight gain, delayed sexual maturation in females, and bilateral corneal crystals at the mid and high doses.
Corneal crystals were still observed at the mid and high doses after a three-week recovery period.
Neurobehavioral deficits were observed on a learning and memory task at the high dose.
A no-effect dose for adverse effects on postnatal development not identified.

Quoted from the official label, section “Pediatric Use”.

Use in older people

Tizanidine is known to be substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in patients with impaired renal function.
Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.
Clinical studies of tizanidine did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently than younger subjects.
Pharmacokinetic data showed that younger subjects cleared tizanidine faster than the elderly subjects [see Clinical Pharmacology (12.3) ] .
In elderly patients with renal insufficiency (creatinine clearance <25 mL/min), tizanidine clearance is reduced compared to healthy elderly subjects; this would be expected to lead to a longer duration of clinical effect.
During titration, the individual doses should be reduced.
If higher doses are required, individual doses rather than dosing frequency should be increased.
Monitor elderly patients because they may have an increased risk for adverse reactions associated with tizanidine.

Quoted from the official label, section “Geriatric Use”.

Side effects

The most common adverse reactions (greater than 10% of patients taking tizanidine and greater than in patients taking placebo) were dry mouth, somnolence, asthenia, and dizziness.
( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Zydus Pharmaceuticals USA Inc. at 1-877-993-8779, or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
The following clinically significant adverse reactions are described elsewhere in other sections of the prescribing information:
Hypotension [ see Warnings and Precautions (5.1) ] Liver Injury [ see Warnings and Precautions (5.2) ] Sedation [ see Warnings and Precautions (5.3) ] Hallucinosis/Psychotic-Like Symptoms [ see Warnings and Precautions (5.4) ] Hypersensitivity Reactions [see Warnings and Precautions ( 5.5 )] Withdrawal Adverse Reactions [see Warnings and Precautions (5.6 )]
6.1 Clinical Trials Experience Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug and may not reflect the rates observed in clinical practice.
The safety of tizanidine has been evaluated in three double-blind, randomized, placebo-controlled clinical studies [see Clinical Studies (14) ] .
Two studies were conducted in patients with multiple sclerosis and one in patients with spinal cord injury.
Each study had a 13-week active treatment period which included a 3-week titration phase to the maximum tolerated dose up to 36 mg/day in three divided doses, a 9-week plateau phase where the dose of tizanidine was held constant and a 1-week dose tapering period.
In all, 264 patients received tizanidine and 261 patients received placebo.
Across the three studies approximately 51% of patients were women, and the median dose during the plateau phase ranged from 20 to 28 mg/day.
The most common adverse reactions (>10% of patients treated with tizanidine) reported in multiple dose, placebo-controlled clinical studies involving 264 patients with spasticity were dry mouth, somnolence/sedation, asthenia (weakness, fatigue and/or tiredness), and dizziness.
Three-quarters of the patients rated the reactions as mild to moderate and one-quarter of the patients rated the reactions as being severe.
These adverse reactions appeared to be dose related.
Table 1 lists adverse reactions that were reported in greater than 2% of patients in three multiple dose, placebo-controlled studies who received tizanidine where the frequency in the tizanidine group was greater than the placebo group.
Table 1:
Multiple Dose, Placebo-Controlled Studies - Adverse Reactions Reported in >2% of Patients Treated with Tizanidine Tablets and Incidence Greater than Placebo Adverse Reaction Placebo N = 261 % Tizanidine Tablet N = 264 % Dry mouth 10 49 Somnolence 10 48 Asthenia * 16 41 Dizziness 4 16 UTI 7 10 Infection 5 6 Constipation 1 4 Liver test abnormality 2 6 Vomiting 0 3 Speech disorder 0 3 Amblyopia (blurred vision) <1 3 Urinary frequency 2 3 Flu syndrome 2 3 Dyskinesia 0 3 Nervousness <1 3 Pharyngitis 1 3 Rhinitis 2 3 * includes weakness, fatigue, and/or tiredness In the single dose, placebo-controlled study involving 142 patients with spasticity due to multiple sclerosis (Study 1) [ see Clinical Studies (14) ] , the patients were specifically asked if they had experienced any of the four most common adverse reactions:
dry mouth, somnolence (drowsiness), asthenia (weakness, fatigue and/or tiredness), and dizziness.
In addition, hypotension and bradycardia were observed.
The occurrence of these reactions is summarized in Table 2.
Other events were, in general, reported at a rate of 2% or less.
Table2:SingleDose , Placebo-ControlledStudy—CommonAdverseReactionsReported Adverse Reaction Placebo N = 48 % Tizanidine Tablet , 8 mg , N = 45 % Tizanidine Tablet , 16 mg , N = 49 % Somnolence 31 78 92 Dry mouth 35 76 88 Asthenia * 40 67 78 Dizziness 4 22 45 Hypotension 0 16 33 Bradycardia 0 2 10 includes weakness, fatigue, and/or tiredness
6.2 Postmarketing Experience The following adverse reactions have been identified during post approval use of tizanidine.
Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
Cardiac Disorders:
Ventricular tachycardia, decreased blood pressure Hepatobiliary Disorders:
Hepatotoxicity [see Warnings and Precautions (5.2) ] , hepatitis Musculoskeletal and Connective Tissue Disorders:
arthralgia Nervous System Disorders:
Convulsion, paresthesia, tremor, muscle spasms Psychiatric Disorders:
Hallucinations [see Warnings and Precautions (5.4) ], depression Skin and Subcutaneous Tissue Disorders:
Stevens Johnson Syndrome, anaphylactic reaction [see Warnings and Precautions (5.5) ] , exfoliative dermatitis, rash

Quoted from the official label, section “Adverse Reactions”.

What to discuss with your doctor

Serious Drug Interactions Advise patients they should not take tizanidine if they are taking fluvoxamine or ciprofloxacin because of the increased risk of serious adverse reactions including severe lowering of blood pressure and sedation.
Instruct patients to inform their healthcare providers when they start or stop taking any medication because of the risks associated with interaction between tizanidine and other medicines [see Contraindications (4) and Drug Interactions (7) ] .
Tizanidine Dosing and Administration Tell patients to take tizanidine exactly as prescribed (consistently either with or without food) and not to switch between tablets and capsules [see Dosage and Administration (2) ] .
Inform patients that they should not take more tizanidine than prescribed because of the risk of adverse events at single doses greater than 8 mg or total daily doses greater than 36 mg.
Tell patients that they should not suddenly discontinue tizanidine, because rebound hypertension and tachycardia may occur [see Warnings and Precautions (5.6) ] .
Hypotension Warn patients that they may experience hypotension and to be careful when changing from a lying or sitting to a standing position [see Warnings and Precautions (5.1) ] .
Sedation Tell patients that tizanidine may cause them to become sedated or somnolent and they should be careful when performing activities that require alertness, such as driving a vehicle or operating machinery [see Warnings and Precautions (5.3) ] .
Tell patients that the sedation may be additive when tizanidine is taken in conjunction with drugs (baclofen, benzodiazepines) or substances (e.g., alcohol) that act as CNS depressants.
Remind patients that if they depend on their spasticity to sustain posture and balance in locomotion, or whenever spasticity is utilized to obtain increased function, that tizanidine decreases spasticity and caution should be used.
Hypersensitivity Reactions Inform patients of the signs and symptoms of severe allergic reactions and instruct them to discontinue tizanidine and seek immediate medical care should these signs and symptoms occur [see Warnings and Precautions (5.5) ].
Brands listed are the trademarks of their respective owners.
Manufactured by: Zydus Lifesciences Ltd., Matoda, Ahmedabad, India Rev.: 12/25

Quoted from the official label, section “Patient Counseling Information”.

Strengths and forms

FORMS AND STRENGTHS Capsules:
2 mg, 4 mg, or 6 mg ( 3 ) Capsules 2 mg:
Light yellow to yellow colored granular powder filled in size "5" empty hard gelatin capsule having light blue opaque colored cap imprinted with "1111" in black ink and light blue opaque colored body. 4 mg:
Light yellow to yellow colored granular powder filled in size "3" empty hard gelatin capsule having violet opaque colored cap imprinted with "1112" in white ink and white opaque colored body. 6 mg:
Light yellow to yellow colored granular powder filled in size "2" empty hard gelatin capsule having violet opaque colored cap imprinted with "1113" in white ink and violet opaque colored body.

Quoted from the official label, section “Dosage Forms & Strengths”.

What it looks like and how it is packed

16.1 How Supplied Tizanidine Capsules, 2 mg are light yellow to yellow colored granular powder filled in size "5" empty hard gelatin capsule having light blue opaque colored cap imprinted with "1111" in black ink and light blue opaque colored body and are supplied as follows:
NDC 70771-1067-8 in bottles of 150 capsules with child-resistant closure NDC 70771-1067-5 in bottles of 500 capsules NDC 70771-1067-4 in unit-dose blister cartons of 100 (10 x 10) unit-dose capsules Tizanidine Capsules, 4 mg are light yellow to yellow colored granular powder filled in size "3" empty hard gelatin capsule having violet opaque colored cap imprinted with "1112" in white ink and white opaque colored body and are supplied as follows:
NDC 70771-1068-8 in bottles of 150 capsules with child-resistant closure NDC 70771-1068-5 in bottles of 500 capsules NDC 70771-1068-4 in unit-dose blister cartons of 100 (10 x 10) unit-dose capsules Tizanidine Capsules, 6 mg are light yellow to yellow colored granular powder filled in size "2" empty hard gelatin capsule having violet opaque colored cap imprinted with "1113" in white ink and violet opaque colored body and are supplied as follows:
NDC 70771-1069-8 in bottles of 150 capsules with child-resistant closure NDC 70771-1069-5 in bottles of 500 capsules NDC 70771-1069-4 in unit-dose blister cartons of 100 (10 x 10) unit-dose capsules
Storage and Handling
Store at 20° to 25°C (68° to 77°F) [See USP Controlled Room Temperature].
Dispense in containers with child resistant closure.

Quoted from the official label, section “How Supplied”.

What is in it

Tizanidine capsules contains tizanidine hydrochloride as the active ingredient, which is a central alpha 2 -adrenergic agonist.
Its chemical name is 5-chloro-4-(2-imidazolin-2-ylamino)-2,1,3-benzothiadiazole monohydrochloride.
It has a molecular formula of C 9 H 8 ClN 5 S-HCl and a molecular weight of 290.2.
Its structural formula is:
Tizanidine Hydrochloride is a white to slightly yellow crystalline powder.
Tizanidine Hydrochloride is soluble in water and methanol.
Tizanidine capsule are for oral administration and contains 2 mg or 4 mg or 6 mg tizanidine (equivalent to 2.29 mg or 4.58 mg or 6.87 mg tizanidine hydrochloride, respectively), the inactive ingredients:
colloidal silicon dioxide, croscarmellose sodium, hypromellose, lactose monohydrate, microcrystalline cellulose and stearic acid.
Each capsule shell contains fd & c blue # 1, fd & c red # 3, gelatin and titanium dioxide.
The 2 mg capsule is printed with black pharmaceutical ink which contains black iron oxide, potassium hydroxide and shellac; 4 mg and 6 mg capsule is printed with white pharmaceutical ink which contains potassium hydroxide, shellac and titanium dioxide. figure

Quoted from the official label, section “Description”.

Ingredients people check for

Lactose, gluten, dyes, sugars and other ingredients that matter with an allergy, intolerance or diet — as this product’s FDA label lists them.

Lactoselactose monohydrateMilk sugar: matters with lactose intolerance or a milk allergy.

Quoted from the FDA label. A label that does not name an ingredient is not a guarantee that the product is free of it, and formulations change. With an allergy, check the pack and ask a pharmacist.

Every version of this medicine (19)

The same active substance, strength and kind of form, from every company that sells it — with what each label lists.

Showing 19 of 19

Details

Made by	Zydus Lifesciences Limited
Active substance	Tizanidine Hydrochloride
Used in	Heart, blood pressure and circulation
Strength	4 mg
Form	Capsule
Route	Oral
Packs	10 BLISTER PACK in 1 CARTON / 10 CAPSULE in 1 BLISTER PACK · 500 CAPSULE in 1 BOTTLE
NDC	70771-1068

Source: NDC Directory · 2026-09-13 · not reviewed by a clinician

Source: US Food and Drug Administration, NDC Directory. Reuse terms: US government work (FDA).

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Other strengths and forms

54 products are sold under this name. Grouped by form; a number on a strength means several companies make it.

Capsule45 products
- 2 mg12
  2 mg · 12 companies
  +4 more
- 4 mg15
  4 mg · 15 companies
  +7 more
- 6 mg16
  6 mg · 16 companies
  +8 more
- 8 mg2
  8 mg · 2 companies
  - Advagen Pharma Limited
  - Trifluent Pharma, LLC
Capsule, Gelatin Coated7 products
- 2 mg2
  2 mg · 2 companies
  - Actavis Pharma, Inc.
  - Apotex Corp.
- 4 mg3
  4 mg · 3 companies
- 6 mg2
  6 mg · 2 companies
  - Actavis Pharma, Inc.
  - Apotex Corp.
Tablet2 products
- 4 mg2
  4 mg · 2 companies
  - Quality Care Products LLC
  - TIZANIDINE HYDROCHLORIDE

Same active substance

These contain the same substance. That does not mean one can replace another — ask a pharmacist.

See every product with Tizanidine Hydrochloride