Carisoprodol: uses, side effects and safety
Carisoprodol (Soma) is a skeletal muscle relaxant (centrally acting). It is a US Schedule IV controlled substance. It is prescription only (rx) and remains on the US market.
What is Carisoprodol?
Carisoprodol is the generic name for Soma, and belongs to the Skeletal muscle relaxant (centrally acting) class.
| Generic name | carisoprodol |
|---|---|
| Brand name(s) | Soma |
| Drug class | Skeletal muscle relaxant (centrally acting) |
| US legal status | US Schedule IV ยท Prescription only (Rx) |
| Route | Oral |
| Prescription required | Yes |
| Elimination half-life | Terminal elimination half-life of carisoprodol approximately 2 hours (1.7 +/- 0.5 hours at 250 mg; 2.0 +/- 0.5 hours at 350 mg); half-life of the active metabolite meprobamate approximately 10 hours (9.7 +/- 1.7 and 9.6 +/- 1.5 hours respectively) |
| Time to peak concentration | 1.5 +/- 0.8 hours at 250 mg; 1.7 +/- 0.8 hours at 350 mg |
| Metabolism | The major pathway of carisoprodol metabolism is via the liver by cytochrome enzyme CYP2C19 to form meprobamate |
What is Carisoprodol used for?
Carisoprodol is approved by the FDA for the following uses. Approval is granted per indication, and a specific product may not be approved for all of them.
- Relief of discomfort associated with acute, painful musculoskeletal conditions (treatment limited to short term, up to three weeks)
How does Carisoprodol work?
The mechanism of action of carisoprodol in relieving discomfort associated with acute painful musculoskeletal conditions has not been clearly identified; in animal studies, muscle relaxation induced by carisoprodol is associated with altered interneuronal activity in the spinal cord.
It is metabolised primarily by The major pathway of carisoprodol metabolism is via the liver by cytochrome enzyme CYP2C19 to form meprobamate.
The elimination half-life is roughly Terminal elimination half-life of carisoprodol approximately 2 hours (1.7 +/- 0.5 hours at 250 mg; 2.0 +/- 0.5 hours at 350 mg); half-life of the active metabolite meprobamate approximately 10 hours (9.7 +/- 1.7 and 9.6 +/- 1.5 hours respectively). Longer half-lives mean the drug and its active metabolites persist in the body for longer after the last dose.
Common side effects of Carisoprodol
These are the side effects people report most often. Many diminish after the body adjusts, usually within one to two weeks.
- Controlled studies: drowsiness 13% (250 mg) to 17% (350 mg), dizziness 8% and 7%, headache 5% and 3%
- Vertigo
- Tremor
- Agitation
- Irritability
- Nausea and vomiting
What does Carisoprodol interact with?
Interactions matter because two safe medicines can become dangerous together. The entries below are the ones most likely to cause harm.
- CNS depressants (e.g., alcohol, benzodiazepines, opioids, tricyclic antidepressants): additive sedative effects
- Concomitant use of carisoprodol and meprobamate is not recommended
- CYP2C19 inhibitors such as omeprazole or fluvoxamine can increase carisoprodol exposure
- CYP2C19 inducers such as rifampin, carbamazepine, phenobarbital, or St. John's Wort can decrease carisoprodol exposure and increase meprobamate exposure
Use our drug interaction checker before combining any two prescriptions.
Serious side effects and warning signs
Seek emergency care for any of these
- Seizures
- CNS and respiratory depression
- Coma
- Hypotension and postural hypotension
- Postmarketing: leukopenia and pancytopenia
- Postmarketing: tachycardia, facial flushing, syncope
Suspected overdose or a bad reaction should be reported to Poison Control on 1-800-222-1222. That is staffed around the clock and is free.
Legal status of Carisoprodol
Carisoprodol is a Schedule IV controlled substance in the United States. That placement is set out in Title 21 of the Code of Federal Regulations, Part 1308, and enforced by the Drug Enforcement Administration. It carries restrictions on prescribing, storage, record-keeping and transfer.
Statutory reference: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=069ea892-21a6-4703-8dd3-bf19c4406479.
Can you get Carisoprodol without a prescription?
Short answer: no. Carisoprodol is a prescription medication. Sites advertising it without one are either operating illegally or selling something other than what they claim. We explain the legal routes, the counterfeit problem and how to check a source in detail.
Read the full answer: Carisoprodol without a prescription →
Related medications
Butalbital
Barbiturate (butalbital) combination analgesicRelief of the symptom complex of tension (or muscle contraction) headache
Read more →Frequently asked questions
What is Carisoprodol used for?
Relief of discomfort associated with acute, painful musculoskeletal conditions (treatment limited to short term, up to three weeks)
What schedule is Carisoprodol in the United States?
Carisoprodol is a Schedule IV controlled substance in the US, listed at 21 CFR Part 1308. Schedule IV means the drug has a defined potential for abuse and is subject to federal record-keeping, storage and prescribing restrictions.
What are the common side effects of Carisoprodol?
The most frequently reported side effects are controlled studies: drowsiness 13% (250 mg) to 17% (350 mg), dizziness 8% and 7%, headache 5% and 3%, vertigo, tremor, agitation, irritability, nausea and vomiting. Many lessen over the first week or two of treatment.
What should not be combined with Carisoprodol?
The most clinically important interactions are with cns depressants (e.g., alcohol, benzodiazepines, opioids, tricyclic antidepressants): additive sedative effects, concomitant use of carisoprodol and meprobamate is not recommended, cyp2c19 inhibitors such as omeprazole or fluvoxamine can increase carisoprodol exposure, cyp2c19 inducers such as rifampin, carbamazepine, phenobarbital, or st. john's wort can decrease carisoprodol exposure and increase meprobamate exposure. Always give a pharmacist or prescriber a complete list of everything you take, including over-the-counter drugs and supplements.
Sources & references
Important
This site provides educational information only and does not sell, prescribe or dispense medications. Always consult a licensed healthcare provider. This page is not medical advice.