Metaxalone Side Effects

Medically reviewed by Drugs.com. Last updated on May 12, 2024.

Applies to metaxalone: oral tablet.

Precautions

It is very important that your doctor check your and your child's progress at regular visits to make sure this medicine is working properly and to check for unwanted effects.

Check with your doctor right away if you have anxiety, restlessness, a fast heartbeat, fever, sweating, muscle spasms, twitching, nausea, vomiting, diarrhea, or see or hear things that are not there. These may be symptoms of a serious condition called serotonin syndrome. Your risk may be higher if you also take certain other medicines that affect serotonin levels in your body or if you take metaxalone for a long time.

This medicine may make you dizzy, drowsy, or less alert than you are normally. These effects may be increased if you take this medicine with food. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.

Check with your doctor before using this medicine with alcohol or other medicines that affect the central nervous system (CNS). The use of alcohol or other medicines that affect the CNS with metaxalone may worsen the side effects of this medicine, such as dizziness, poor concentration, drowsiness, unusual dreams, and trouble with sleeping. Some examples of medicines that affect the CNS are antihistamines or medicine for allergies or colds, sedatives, tranquilizers, or sleeping medicines, medicine for depression, medicine for anxiety, prescription pain medicine or narcotics, medicine for attention deficit and hyperactivity disorder, medicine for seizures or barbiturates, other muscle relaxants, or anesthetics, including some dental anesthetics.

Make sure any doctor or dentist who treats you knows that you are using this medicine. This medicine may affect the results of certain medical tests.

Common side effects of metaxalone

Some side effects of metaxalone may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Serious side effects of metaxalone

Along with its needed effects, metaxalone may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking metaxalone:

For healthcare professionals

Applies to metaxalone: oral tablet.

General adverse events

The most frequent reactions were drowsiness, dizziness, headache, irritability, nausea, vomiting and gastrointestinal upset.^[Ref]

Gastrointestinal

• Frequency not reported: Nausea, vomiting, gastrointestinal upset^[Ref]

Hematologic

• Frequency not reported: Leukopenia, hemolytic anemia^[Ref]

Hepatic

• Frequency not reported: Jaundice^[Ref]

Hypersensitivity

• Frequency not reported: Anaphylaxis, hypersensitivity reaction, rash (with or without pruritus)^[Ref]

Nervous system

• Frequency not reported: Serotonin syndrome, drowsiness, dizziness, headache^[Ref]

Other

• Frequency not reported: False-positive Benedict's tests (due to an unknown reducing substance)^[Ref]

A glucose-specific test may be used to differentiate findings.^[Ref]

Psychiatric

• Common (1% to 10%): Nervousness, irritability^[Ref]

See also:

Further information

Metaxalone side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer