Tizanidine, sold under the brand name Zanaflex among others, is a medication that belongs to a class of drugs called skeletal muscle relaxants. It works by slowing action in the brain and nervous system to allow the muscles to relax. Tizanidine is used to relieve the spasms and increased muscle tone caused by multiple sclerosis (MS, a disease in which the nerves do not function properly and patients may experience weakness, numbness, loss of muscle coordination and problems with vision, speech, and bladder control), stroke, or brain or spinal injury.
Effectiveness appears similar to baclofen or diazepam. It is taken by mouth and works by blocking nerve impulses (pain sensations) that are sent to your brain. Tell your doctor right away if you have any serious side effects, such as: fainting, mental/mood changes (such as hallucinations), slow/irregular heartbeat, vision changes (such as blurred vision). Tizanidine has rarely caused very serious (rarely fatal) liver disease.
What drugs interact with tizanidine?
Before taking tizanidine,
- tell your doctor and pharmacist if you are allergic to tizanidine or any other medications.
- tell your doctor if you are taking ciprofloxacin (Cipro) or fluvoxamine. Your doctor will probably tell you not to take tizanidine if you are taking either of these medications.
- tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: acyclovir (Zovirax); amiodarone (Cordarone, Pacerone); baclofen; cimetidine (Tagamet); clonidine (Catapres, Catapres-TTS); dantrolene (Dantrium); diazepam (Valium); famotidine (Pepcid, Pepcid AC); medications for anxiety, seizures, or high blood pressure; mexiletine (Mexitil); oral contraceptives (birth control pills); propafenone (Rythmol); fluoroquinolones such as gemifloxacin (Factive), levofloxacin (Levaquin), moxifloxacin (Avelox), norfloxacin (Noroxin), and ofloxacin (Floxin); ticlopidine (Ticlid); sedatives; sleeping pills; tranquilizers; verapamil (Calan, Covera, Isoptin, Verelan); and zileuton (Zyflo). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Other medications may also interact with tizanidine, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
- tell your doctor if you have or have ever had kidney or liver disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking tizanidine, call your doctor.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking tizanidine.
- you should know that this medication may make you drowsy. Do not drive a car or operate machinery until you know how this medication affects you.
- remember that alcohol can add to the drowsiness caused by this medication.
- you should know that tizanidine may cause dizziness, lightheadedness, and fainting when you get up too quickly from a lying position. This is more common when you first start taking tizanidine. To avoid this problem, get out of bed slowly, resting your feet on the floor for a few minutes before standing up. tizanidine can decrease muscle tone, so be careful when walking or doing other activities where you rely on your muscle tone to help with your posture or balance.
What special dietary instructions should I follow?
Unless your doctor tells you otherwise, continue your normal diet.
What other information should I know?
Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your response to tizanidine. Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.