What are Zanaflex (tizanidine) side effects?

Some of the common Zanaflex side effects are listed below. Please contact your doctor if these symptoms are severe or do not improve over time.

• Dry mouth
• Drowsiness
• Weakness
• Dizziness
• Urinary tract infection
• Diarrhea, vomiting, constipation, stomach pain, heartburn
• Back pain
• Rash
• Sweating
• Tingling in the hands and feet
• Depression
• Nervousness

Some Zanaflex side effects can be more serious. Get in touch with your doctor without delay if you experience the following adverse effects:

• Abnormal bruising or bleeding
• Extreme tiredness, lack of energy
• Itching, yellowing of the eyes or skin
• Loss of appetite, stomach pain in the upper right abdomen
• Flu-like symptoms
• Hallucinations (seeing or hearing things that are not there)
• Vision changes
• Slow heartbeat

The above list may not include all the possible side effects of Zanaflex. Talk to your doctor if you have severe side effects or your symptoms do not improve over time. You can also report unusual Zanaflex side effects to the Food and Drug Administration at 1-800-FDA-1088.

Zanaflex overdose: In case of a known or suspected Zanaflex overdose, call your doctor or the poison control center on 1-800-222-1222 immediately. If a person can’t be awakened, has had a seizure, or has trouble breathing, call 911 without delay. Symptoms of Zanaflex overdose may include extreme tiredness, confusion, drowsiness, slow heartbeat, dizziness, fainting, shallow or slow breathing, and loss of consciousness. 

NOTE: Zanaflex is a prescription drug to be used only by you. Never share your Zanaflex prescription with others or use someone else’s medication.

Source: FDA