Side Effects of Methocarbamol (Robaxin)
Methocarbamol, also known as the common brand Robaxin, belongs to the group of medicines called muscle relaxants and is used for the short-term treatment of pain and muscle spasms caused by injuries such as sprains and strains.
Warnings Before Taking Robaxin
The Robaxin label reported by the FDA affirms Robaxin should not be taken if you have:
- Allergy or allergies to medicines containing methocarbamol or to any of the other ingredients in methocarbamol
- History of any brain damage or coma
- A diagnosis of epilepsy or convulsions
- Myasthenia gravis (a muscle weakness condition)
Tell your doctor or pharmacist before taking Robaxin if you are pregnant or thinking of becoming pregnant, are breastfeeding, have, or have had any kidney or liver problems. Robaxin can also interfere with the results of some of the medical investigations or screening tests.
Serious Side Effects
The severe side effects of Robaxin are: jaundice (yellowing of the skin and/or whites of the eyes), leukopenia (levels of white blood cells reducing) leading to recurrent infections and mouth ulcers, drowsiness, difficulty in sleeping, restlessness, anxiety or worry, dizziness, memory loss, blurred or double vision, rapid or unusual eye movements, reddening of the eyes together with nasal stuffiness (Robaxin label listed by the FDA).
Other serious side effects of Robaxin are:
- Feeling sick or vomiting
- Taste disturbance or loss
- Tremor or shakiness
- Mild muscle incoordination
- Slow heartbeat
- Fainting or feeling faint
- Low blood pressure
When to Contact Your Doctor
In case of experiencing confusion, convulsions, fits, and rash or swelling of the face or neck and shortness of breath which may be a sign of an allergy, methocarbamol should be stopped and treating physician should be informed immediately.
Robaxin may interact with the following medications: barbiturates (taken for epilepsy or to help in sleeping), appetite suppressants to help lose weight, anti-cholinergics (medicines for stomach upsets or sea-sickness), and psychotropic drugs for the treatment of anxiety, depression or other mental illnesses. In addition, if you are due to have anesthetic for any reason; inform your doctor or dentist that you are taking Robaxin.
Patients should be cautioned that Robaxin causes drowsiness or sleepiness, which may impair their ability to operate motor vehicles or machinery. Drinking alcohol should also not be combined while taking Robaxin because it can worsen this effect.
About Pharmacogenetic Testing
Certain individuals will not experience the adverse reactions of Robaxin while others may. The study of pharmacogenetics explains this occurs because of gene variations in how they metabolize medications. Each individual’s genes interacts differently to drugs.
Know Your Risk with the Rxight® Genetic Test
Rxight® is based off the analysis of 18 genes to determine how your body metabolizes over 200 prescription and over-the-counter (OTC) medications. Your Rxight® results will show you and your healthcare provider what medications are effective and the optimal dosages. This guides you, your doctor, and pharmacist to know which medications are right for you.
Contributors to this Article:
Michael Sapko, MD, PhD; and Deborah Kallick, PhD, Medicinal Chemistry
Read more about Rxight® DNA Testing for Medications