was successfully added to your cart.

Side Effects of Metaxalone (Skelaxin)


Side Effects of Metaxalone (Skelaxin)

Metaxalone, available under the brand Skelaxin, is a muscle relaxant which works in the brain to help relax the muscles. Skelaxin is used for treating discomfort associated with acute painful muscle conditions along with rest, physical therapy, or other measures.

Precautions Before Taking Skelaxin

The FDA advises Skelaxin should not be used in case of the presence of any allergy or allergies to any ingredient in metaxalone, known tendency for drug-induced, hemolytic, or other anemias (a lack of red blood cells), severe liver or kidney problems, or if taking sodium oxybate (GHB).


If you intend to take Skelaxin, you should inform your healthcare provider if you have any medical conditions or any of the the following: if you are pregnant or plan to become pregnant, Skelaxin may harm your unborn child, if you are breast feeding a baby, inform your doctor as it is not known if Skelaxin excretes into breast milk, if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement, have allergies to medicines, foods, or other substances, and have a presence of enlarged prostate gland, liver or kidney problems, or have the blood disease porphyria.

Serious Side Effects

These are the severe side effects of Skelaxin:


  • Severe rash, hives, or itching
  • Difficulty breathing
  • Tightness in the chest
  • Swelling of the mouth, face, lips, or tongue
  • Fever
  • Chills
  • Sore throat
  • Unusual or severe tiredness or weakness
  • Jaundice (yellowing of the skin or eyes)
  • Nausea
  • Stomach pain
  • Loss of appetite
  • Dark urine
  • Clay-colored stools


(Skelaxin label reported by the FDA).

Common Side Effects

The most frequent adverse reactions associated with Skelaxin as listed by the Skelaxin label by the FDA, are: dizziness, drowsiness, headache, irritability, nausea, nervousness, upset stomach, and vomiting.

Drug Interactions

Patients should discuss with their health care provider if they are taking any other medicines, especially any of the following: benzodiazepines (diazepam), narcotic pain medicines, such as codeine, or tricyclic antidepressants (amitriptyline) because the risk of drowsiness may be increased, and sodium oxybate (GHB) because an increase in sleep duration and a decrease in the ability to breathe are likely to occur.


When combined with alcohol or other CNS depressants, Skelaxin may impair mental or physical abilities required for performance of hazardous tasks, such as operating machinery or driving a motor vehicle. Taking Skelaxin with food may enhance general CNS depression. Elderly patients are more prone to general CNS depression. Safety and effectiveness in children 12 years of age and below have not been established.

About Pharmacogenetic Testing

Pharmacogenetic testing analyzes gene variations that identify the encoding enzymes responsible for metabolizing drugs. Pharmacogenetic testing shows how gene variants in drug metabolism genes can predict how a patient will react to a medication. An individual who experiences adverse reactions or is more prone to them is a “poor metabolizer” of a drug. An “extensive metabolizer” is one who does not feel the therapeutic benefits of the medication. Being a poor or extensive metabolizer poses the problem of not knowing which medications are best for you.

Know Your Risk with the Rxight® Genetic Test

Rxight® analyzes over 200 prescription and over-the-counter (OTC) medications and how your body metabolizes them. Rxight® collects your DNA through a simple cheek swab test providing your pharmacist information on how your body will respond to a medication. This allows your pharmacist to design a personalized treatment plan with the right medications without the adverse drug reactions.


To learn more about Rxight® contact us at 1-888-888-1932 or at support@Rxight.com.


Contributors to this Article:
Michael Sapko, MD, PhD; and Deborah Kallick, PhD, Medicinal Chemistry

Read more about Rxight® : What is Pharmacogenetics?