Medically Reviewed on 8/18/2022

Generic Name: tizanidine

Brand Name: Zanaflex

Drug Class: Alpha2 Adrenergic Agonists

What is tizanidine, and what is it used for?

Tizanidine is a skeletal muscle relaxant. It works on alpha2 receptors in the central nervous system (brain and spinal cord) and blocks nerve impulses from reaching muscles which produces muscle relaxation.

Tizanidine is used for the treatment and management of skeletal muscle spasticity. Spasticity may be due to multiple sclerosis or spinal cord injury.

The FDA approved tizanidine in November 1996.

What are the side effects of tizanidine?

Common side effects of tizanidine include:

What is the dosage for tizanidine?

  • Initially take 2 - 4 mg by mouth every 6 to 8 hours for up to 3 doses in 24 hours.
  • Increase by 2 to 4 mg until satisfactory response is achieved; however, the maximum dose is 36 mg per day.

Which drugs interact with tizanidine?

Tizanidine should not be used with:

These medications can slow down the breakdown of tizanidine and lead to increased sedation, drowsiness and slowed reflexes.

Tizanidine should be used with caution with medications like:

These medications can further increase the side effects of tizanidine.


Pictures of the 7 Riskiest Workout Moves, and How to Improve Them See Slideshow

Is tizanidine safe to take if I'm pregnant or breastfeeding?

  • There are no adequate studies done on tizanidine to determine safe and effective use in pregnant women.
  • It is not known whether tizanidine enters human milk. Because it is soluble in lipids, it might pass into breast milk.

What else should I know about tizanidine?

What preparations of tizanidine are available?
  • Yes
What preparations of tizanidine are available?
  • Capsules: 2, 4, 6 mg; Tablets: 2, 4 mg
How should I keep tizanidine stored?
  • Store tizanidine tablets and capsules between temperatures of 15 C – 30 C (59 F – 86 F).


Tizanidine is a drug used to treat the tendency of muscles to spasm, typically resulting from neurological problems. Common side effects of tizanidine include low blood pressure, dry mouth, dizziness, sleepiness, weakness, fatigue, blurred vision, and constipation. Consult your doctor if pregnant or breastfeeding.

Treatment & Diagnosis

Medications & Supplements

FDA Logo

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

Medically Reviewed on 8/18/2022
Medically reviewed by John P. Cunha, DO, FACOEP; Board Certified Emergency Medicine


FDA Prescribing Information