Tizanidine Consumer Information

tizanidine

Generic Name: tizanidine (tye ZAN i deen)
Brand Names: Zanaflex

What is tizanidine?

Tizanidine is a short-acting muscle relaxer. It works by blocking nerve impulses (pain sensations) that are sent to your brain.

Tizanidine is used to treat spasticity by temporarily relaxing muscle tone.

Tizanidine may also be used for purposes other than those listed in this medication guide.

What is the most important information I should know about tizanidine?

Tizanidine is a short-acting medication that should be taken only for daily activities that require relief from muscle spasticity.

Switching between tizanidine tablets and capsules, or changing the way you take it with regard to eating, can cause an increase in side effects or a decrease in therapeutic effect. Follow your doctor's instructions carefully. After making any changes in how you take tizanidine, contact your doctor if you notice any change in how well the medicine works or if it causes increased side effects.

What should I discuss with my healthcare provider before taking tizanidine?

Before using tizanidine, tell your doctor if you are allergic to any drugs, or if you have:

• liver disease;

• kidney disease;

• high or low blood pressure; or

• a history of "Long QT syndrome."

If you have any of these conditions, you may not be able to use tizanidine, or you may need a dosage adjustment or special tests during treatment.

How should I take tizanidine?

Take this medication exactly as it was prescribed for you. Do not take the medication in larger amounts, or take it for longer than recommended by your doctor. Follow the directions on your prescription label.

Your doctor may occasionally change your dose to make sure you get the best results from this medication.

Tizanidine is a short-acting medication, and its effects will be most noticeable between 1 and 6 hours after you take it. This medication should be taken only for daily activities that require relief from muscle spasticity.

In most cases, you may take up to three doses in one day if needed. Allow 6 to 8 hours to pass between doses.

Switching between tizanidine tablets and capsules, or changing the way you take it with regard to eating, can cause an increase in side effects or a decrease in therapeutic effect. Follow your doctor's instructions carefully. After making any changes in how you take tizanidine, contact your doctor if you notice any change in how well the medicine works or if it causes increased side effects.

To be sure this medication is not causing harmful effects, your liver function will need to be tested on a regular basis. Do not miss any scheduled visits to your doctor.

You may have withdrawal symptoms such as dizziness, fast heart rate, tremors, anxiety, and increased spasticity when you stop using tizanidine after using it over a long period of time. Do not stop using this medication suddenly without first talking to your doctor. You may need to use less and less before you stop the medication completely.

What happens if I miss a dose?

Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at your next regularly scheduled time. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Overdose symptoms may include drowsiness, confusion, slow heart rate, shallow breathing, feeling light-headed, fainting, or coma.

What should I avoid while taking tizanidine?

Tizanidine side effects

• feeling light-headed, fainting, slow heart rate;

• hallucinations, confusion, unusual thoughts or behavior;

• nausea, stomach pain, low fever, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes); or

• burning or pain when you urinate.

Less serious side effects may be more likely to occur, such as:

• drowsiness or dizziness;

• feeling anxious or nervous;

• numbness or tingling;

• stomach pain, diarrhea, constipation, vomiting;

• fever;

• dry mouth;

• muscle weakness, back pain;

• increased muscle tone or spasms; or

• sweating or skin rash.

This list is not complete and other side effects may occur. Tell your doctor about any unusual or bothersome side effects.

What other drugs will affect tizanidine?

Before taking tizanidine, tell your doctor if you are using any of the following drugs:

• acyclovir (Zovirax);

• cimetidine (Tagamet);

• famotidine (Pepcid);

• ticlopidine (Ticlid),

• zileuton (Zyflo);

• birth control pills;

• antibiotics such as enoxacin (Penetrex), gatifloxacin (Tequin), levofloxacin (Levaquin), lomefloxacin (Maxaquin), moxifloxacin (Avelox), ofloxacin (Floxin), sparfloxacin (Zagam), trovafloxacin (Trovan), or norfloxacin (Noroxin);

• blood pressure medications such as clonidine (Catapres), guanabenz (Wytensin), guanfacine (Tenex), or methyldopa (Aldomet); or

• heart rhythm medications such as amiodarone (Cordarone, Pacerone), mexiletine (Mexitil), propafenone (Rhythmol), and verapamil (Calan, Covera, Isoptin).

This list is not complete and there may be other drugs that can interact with tizanidine. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.