Zanaflex (tizanidine): What it does and how to use it

Zanaflex (generic name tizanidine) is a short-acting muscle relaxant doctors prescribe for muscle spasms and spasticity from conditions like multiple sclerosis or after a back injury. It calms overactive nerves in the spinal cord so muscles relax. People often notice drowsiness or less tightness within a few hours of a dose.

How to take Zanaflex (dosing tips)

Start low. Typical starting dose is 2 mg at night, then your doctor may increase slowly to find the lowest effective dose. Common regimens are 2–4 mg every 6 to 8 hours. Total daily doses usually stay under 36 mg. Take it exactly as prescribed—don’t double doses if you miss one.

Try taking the largest dose at bedtime if drowsiness is a problem. If you have liver problems, your doctor will adjust the dose or avoid Zanaflex entirely. Older adults may need lower doses because they can feel sedation and low blood pressure more strongly.

Side effects, interactions and safety tips

Common side effects: drowsiness, dizziness, dry mouth, low blood pressure, and weakness. If you feel very sleepy, faint, or unusually confused, call your doctor. Zanaflex can lower blood pressure—stand up slowly to avoid lightheadedness.

Watch for liver issues. Rarely, tizanidine can raise liver enzymes. Many clinicians check baseline liver tests and repeat them during treatment.

Major drug interactions: avoid strong CYP1A2 inhibitors like ciprofloxacin and fluvoxamine. These can sharply raise Zanaflex levels and cause severe drowsiness or low blood pressure. Also avoid mixing with alcohol, benzodiazepines, opioids, or other sedatives—combined effects increase dizziness and breathing problems.

Don’t stop suddenly. Stopping Zanaflex abruptly after regular use can cause rebound high blood pressure, fast heart rate, or increased spasticity. Your prescriber will usually taper the dose down.

Practical tips: keep a medication list and show it to every provider or pharmacist. Try Zanaflex when you can rest or are not driving until you know how it affects you. If muscle spasm limits sleep, a single evening dose may help without causing daytime grogginess. Report persistent weakness, yellowing skin, or dark urine—these can be signs of liver trouble.

Comparing options: Zanaflex works faster and shorter than some other muscle relaxants. If you need longer relief, your doctor might suggest alternatives or combine treatments like physical therapy, stretching, or targeted exercise.

Questions to ask your doctor: How long should I try Zanaflex? Do I need liver tests? What medications should I avoid? With clear answers, you’ll know how to use Zanaflex safely and get real relief from muscle tightness.