How Long Does Soma (Carisoprodol) Stay in Your System?

Soma (Carisoprodol) in Your Blood, Urine, Hair, & Saliva

Soma (carisoprodol) is a muscle relaxant and is used to help relieve pain and discomfort caused by strains, sprains, and other muscle injuries.

Soma works by affecting the communication between nerves in the central nervous system. It produces muscle relaxation and pain relief.

Soma is available in tablets and it is also available in combination products that include aspirin or codeine and aspirin. It is taken several times a day as prescribed. You should take Soma with milk or food as it can cause an upset stomach.

How Soma Affects Your System

Carisoprodol is broken down into meprobamate in the body, which is also active in its effects. Carisoprodol is absorbed and begins to have effects after 30 minutes and the effects last for 4 to 6 hours.

Peak concentrations are seen in 1.5 to 2 hours for carisoprodol, and between 3 and 4 hours for its meprobamate metabolite.

The half-life of carisoprodol is about 1 to 3 hours, which varies depending on individual metabolism. The half-life of meprobamate is much longer, between 6 and 17 hours, which can lead to accumulation with multiple doses.

Both carisoprodol and its metabolite meprobamate are excreted in the urine and can be detected for several days after the last dose.


To prevent side effects and drug interactions, be sure to discuss all prescription and nonprescription medications you are taking or plan to take with your doctor. Especially discuss muscle relaxants, sedatives, sleeping pills, tranquilizers, vitamins, and medications for allergies, coughs, or colds.

Your metabolism of Soma can be affected if you have ever had liver or kidney disease.

If you are pregnant, breastfeeding, or plan to become pregnant, discuss with your doctor what the implications may be for taking Soma.

Soma can make you drowsy, so it's important to take precautions for driving or operating machinery.

Side effects can include headache, fast heartbeat, drowsiness, confusion, slowed thinking, upset stomach, skin rash, and sluggish movements.

Severe Side Effects

Soma should be taken exactly as directed. To avoid the following severe side effects, do not take more than prescribed or take it more often than directed by your healthcare provider.

  • Difficulty breathing
  • Fever
  • Weakness
  • Burning in the eyes

Contact your doctor immediately or call 911 if you have any of these symptoms. In very large doses, Soma will produce a meprobamate overdose, which can lead to a coma.

When you stop taking Soma, duration and severity of withdrawal symptoms will depend on how long the drug has been used, the level of tolerance, and the dosage.

How Long Soma Stays in Your System

If you abruptly stop taking Soma, you may experience short-term withdrawal symptoms that can begin 12 to 24 hours after your last dose and usually resolve within 2 to 4 days.

Carisoprodol and meprobamate can be detected on a screen for prescription or over-the-counter drugs in blood and urine, as may be done in the case of a suspected overdose. They typically aren't included in a urine drug screen such as done for employment.

However, if you are taking the combination product that includes codeine, that will be detected. Be sure to disclose your medications to the testing lab so they are able to better interpret the test results.

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7 Sources
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  1. U.S. Food & Drug Administration. Highlights of prescribing information. Soma (carisoprodol) tablets for oral use, CIV. Updated April 2019.

  2. National Center for Biotechnology Information. PubChem Compound Summary for CID 2576, Carisoprodol.

  3. McIntyre IM, Sherrard J, Lucas L. Postmortem Carisoprodol and Meprobamate Concentrations in Blood and Liver: Lack of Significant RedistributionJ Anal Toxicol. 2012;36(3):177-181. doi:10.1093/jat/bks011

  4. Wang G, Huynh K, Barhate R, et al. Validation of a New Homogeneous Immunoassay for the Detection of Carisoprodol in UrineJ Anal Toxicol. 2011;35(2):108-112. doi:10.1093/anatox/35.2.108

  5. MedlinePlus. Carisoprodol. Updated September 28, 2020.

  6. MedlinePlus. Meprobamate overdose. Updated October 8, 2020.

  7. Weiss R. Addiction Resource. Soma Withdrawal And Detox: Symptoms And Timeline.