Worst Pills, Best Pills Review: Carisoprodol (SOMA, SOMA COMPOUND)

In November 2007, the European Medicines Agency (EMEA) proposed removing the widely prescribed, dangerous muscle relaxant carisoprodol (SOMA, SOMA COMPOUND and SOMA COMPOUND with CODEINE) from the market in all European Union countries because “the risks of these medicines outweigh their benefits.”    

A major reason for the proposed ban was evidence that people using the drugs have a significantly increased risk of having a motor vehicle accident in which someone is injured. The EMEA concluded that “there is evidence of increased risk of abuse, addiction, intoxication and psychomotor impairment [such as inability to drive a care safely] associated with the use of carisoprodol. The EMEA has advised patients who are receiving carisoprodol to consult their doctor before stopping the drug due to the risk of withdrawal symptoms.”

The study prompting this appeared in 2007 in the journal Accident Analysis and Prevention suggesting that the well-documented serious side effects of carisoprodol (disorientation, speech or vision problems and temporary inability to move arms or legs) are the likely cause of the increased risk of motor vehicle accidents found in Norway. Using data that included all non-hospital prescriptions filled in Norway and records of all motor vehicle accidents in the country, the researchers found that within the first week of dispensing carisoprodol, a patient’s risk of being involved in an accident in which someone was injured increased 3.7-fold compared to people who were not prescribed the drug. The study adjusted for the use of other drugs by restricting the exposed group to those who did not fill a prescription for other impairing drugs.    

Once again, the U.S. Food and Drug Administration (FDA) lags behind other governments in protecting people from a drug with real potential for disaster, as no plans to ban these drugs have been announced by the FDA. Carisoprodol has been one of the 50 most prescribed generic drugs for at least the past eight years, with 11.9 million prescriptions and $211 million in retail sales during 2007.

In the first edition of Worst Pills, Best Pills, published 20 years ago, we advised our readers not to use these drugs, stating that “Carisoprodol has not been shown to be any more effective than painkillers or anti-inflammatory drugs such as aspirin for relieving the pain of local muscle spasm.”

The side effects experienced by some people taking carisoprodol, which can cause a reaction within the first few minutes or hours after the first dose, are listed in Worst Pills, Best Pills as “drowsiness, lightheadedness, dizziness, nausea, vomiting, heartburn, abdominal distress, constipation, diarrhea, and loss of appetite … agitation, confusion, unsteadiness, disorientation, weakness, speech or vision problems, and temporary inability to move arms or legs.”

A more complete list of side effects of carisoprodol can be found in recent information from the U.S. Government:

Adverse reactions may include central nervous system related effects such as drowsiness, dizziness, vertigo, ataxia (unsteady gait), tremor, agitation, irritability, head ache, depressive reactions, syncope and insomnia. Carisoprodol may also adversely affect cardiovascular (tachycardia [rapid pulse], postural hypotension and facial flushing), gastrointestinal (nausea, vomiting, hiccup and epigastric distress) and hematologic systems. It may cause idiosyncratic symptoms including extreme weakness, transient quadriplegia (weakness of arms and legs), difficulty in speech, temporary loss of vision, double vision, dilated pupils, agitation, euphoria, confusion and disorientation. Carisoprodol overdose has resulted in stupor, coma, shock, respiratory depression and death.

What You Can Do

Patients considering using any drug containing carisoprodol should choose a less dangerous alternative such as aspirin, taken in combination with rest, exercise and physical therapy.

If you are already using the drug, be warned that carisoprodol may have sedative properties and may impair the mental and/or physical abilities required for the performance of potentially hazardous tasks such as driving a motor vehicle or operating machinery. Because the drugs are addictive, consult your doctor before stopping them due to the risk of withdrawal symptoms.