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Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.



COMMON BRAND NAME(S): Paraflex, Parafon Forte, Relaxazone, Remular-S


This medication relaxes muscles and relieves pain and discomfort associated with strains, sprains, spasms or other muscle injuries.

How To Use

Take orally by mouth exactly as directed by your doctor, usually 3 to 4 times daily. Dosage depends on your response and condition. Do not increase your dose, take it more frequently or use it for a longer period than prescribed. Take with food if stomach upset occurs.

Side Effects

May cause stomach upset, heartburn, constipation, headache, dizziness or drowsiness. If these effects persist or worsen, contact your doctor. Inform your doctor if you develop signs of liver problems such as: yellowing of the eyes or skin, fever, unusual fatigue. May discolor urine. This will disappear when the medication is stopped. In the unlikely event you have an allergic reaction to this drug, seek immediate medical attention. Symptoms of an allergic reaction include: rash, itching, swelling, dizziness, trouble breathing. If you notice other effects not listed above, contact your doctor or pharmacist.


Before using this medication, tell your doctor your medical history, especially of: liver problems, stomach or intestinal problems, any drug allergies. Because this drug can cause drowsiness and dizziness, limit alcohol intake. Use caution when performing tasks that require alertness, such as driving. Chlorzoxazone should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor. It is not known if this drug is excreted into breast milk. Consult your doctor before breast-feeding.

Drug Interactions

Tell your doctor of all over-the-counter and prescription medication you may use, especially of drugs that can cause dizziness or drowsiness such as: narcotic pain relievers (e.g., codeine), sleep medication, certain antihistamines (e.g., diphenhydramine), alcohol-containing medications, drugs used for mood/mental conditions. Many cough-and-cold preparations contain ingredients that may add to the drowsiness effects of chlorzoxazone. Consult your doctor or pharmacist before using any such medications. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include nausea, vomiting, diarrhea, unusual drowsiness or dizziness, lightheadedness, and headache.


This medication provides temporary relief and must be used in addition to rest, physical therapy and other measures. Do not allow others to use this medication.

Missed Dose

If you should miss a dose, take it as soon as remembered unless it is almost time for the next dose. If it is nearly time for the next dose, skip the missed dose and resume your usual dosing schedule. Do not "double-up" the dose.


Store at room temperature between 59 and 86 degrees F (between 15 and 30 degrees C) away from moisture and sunlight. Do not store in the bathroom.