Zanaflex (Tizanidine) for Fibromyalgia

Overview
Zanaflex is a prescription medication approved by the Food and Drug Administration (FDA) for treating muscle spasms. Zanaflex is also available as a generic under its drug name, Tizanidine. In cases of fibromyalgia, Zanaflex can help relieve pain.

Zanaflex may not be appropriate for people with low blood pressure or liver or kidney problems, or for pregnant women or women who might become pregnant. Zanaflex may not be suitable for people who are also taking medications that depress the nervous system such as some antihistamines, tranquilizers and antidepressants, narcotic pain relievers, seizure medications, or other muscle relaxants. Zanaflex may be less effective in people who are also taking birth control pills. Ask your doctor about drinking alcohol while taking Zanaflex.

Zanaflex is a muscle relaxant. It is believed that Zanaflex works by inhibiting motor neurons, the nerves that carry signals from the spinal cord to the skeletal muscles.

How do I take it?
Zanaflex is available in three formulations: Zanaflex brand capsules, Zanaflex brand pills, and generic Tizanidine pills. Although the active ingredient in each is identical, instructions for taking the drug, its effectiveness, and some side effects may differ between formulations. Ask your doctor which formulation is best for you, and always discuss with your doctor before switching formulations.

Your doctor may want to test your blood to check your liver function before prescribing Zanaflex and regularly while you are taking Zanaflex.

Depending on the formulation your doctor prescribes, they may tell you to take it with or without food. Follow these directions carefully, since it could impact the drug’s effectiveness and side effects.

Your doctor will likely start you on a very small dosage of Zanaflex, such as 2 milligrams. You may be instructed to increase the dosage gradually over several days, waiting one to four days between increases, until you reach the minimum effective dose. Doses of Zanaflex are usually taken every six to eight hours, with a maximum of three doses per day. Do not take more than 36 milligrams of Zanaflex in 24 hours.

If you have been taking high (20 to 36 milligrams per day) doses of Zanaflex for nine weeks or more, and you decide to stop taking Zanaflex, inform your doctor. They will help you gradually taper off your dosage before stopping completely. If you stop taking Zanaflex suddenly without tapering off, you may suffer symptoms of withdrawal and rebound.

Always follow your doctor’s instructions exactly when taking Zanaflex.

Results
Tizanidine (Zanaflex) was approved by the FDA in 1996 based on clinical trials. Results consistently showed that Tizanidine provided significant relief from muscle spasticity, but did not cause muscle weakness.

Side effects
Several side effects are common when you begin taking Zanaflex, but which usually go away within two weeks. These include dry mouth, drowsiness, increased weakness or tiredness, confusion, dizziness or lightheadedness, back pain, and an increase in muscle cramps or spasms. Contact your doctor if these persist past two weeks, or if they are intolerable.

Other symptoms can include low blood pressure, slow heartbeat and abnormal liver test results.

Some people experience serious symptoms that should be reported to the doctor immediately. These include feelings of burning, prickling or tingling, skin sores, fever, diarrhea, vomiting, loss of appetite, fainting, burning sensation while urinating, jaundice (yellowing of the eyes or skin) and blurred vision.

If you stop taking Zanaflex without tapering off correctly, you may experience symptoms of withdrawal and rebound. In addition to the return of your spasticity symptoms, withdrawal may include high blood pressure, fast heartbeat, tremors, and anxiety.

Zanaflex can also cause allergic reactions. Get medical help immediately if you experience difficulty breathing or swelling of the face, throat, eyes, lips or tongue.