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    Carisoprodol (Soma®) sold as diazepam

  • 19 Feb 2026
     
    • Source: Victorian Pill Testing Service

    What is Carisoprodol (Soma®)?

    Carisoprodol is a muscle relaxant medication used to treat painful musculoskeletal conditions. It was marketed under the trade name Soma®. It is no longer commonly prescribed in Australia.

    Carisoprodol acts similarly to diazepam (Valium®) however it is metabolised into meprobamate, which acts more like a barbiturate by directly binding to GABAA receptors.

    Generally, carisoprodol is considered to have a higher risk of harm than diazepam (Valium®).

    Risks

    • Overdose risk is very high when combining this with any other central nervous system (CNS) depressants like benzos, barbiturates, alcohol, opioids, gabapentinoids or GHB
    • Falling and injury risks at higher doses
    • The drug stays in your system longer than the euphoric effects, so re-dosing has a ‘stacking’ effect which increases the risk of harm
    • Respiratory depression and seizures are a risk

    Carisoprodol requires medical supervision to safely undergo withdrawal if you have a physical dependence.

    Effects – Onset of effects: felt within 30 minutes / Duration: approx. six hours

    • Cognitive and physical euphoria – more intense than benzodiazepines
    • Sedation
    • Nausea / vomiting
    • Dizziness
    • Loss of voluntary muscle coordination, causing unsteadiness, clumsiness, and impaired balance (ataxia)

    Researchers have described carisoprodol as producing an effect similar in some ways to alcohol intoxication.

    Harm Reduction Tips

    • Test it! You may think you know, but it’s best to test and be sure.
    • Carry naloxone. whilst Naloxone will not reverse a carisoprodol overdose, it does reverse an opioid overdose, is legal and widely available
    • Avoid mixing drugs. Carisoprodol mixed with other drugs especially CNS depressants can be dangerous
    • Avoid using alone. Use with people you trust who can help if something goes wrong
    • Start low and go slow. Start with a small amount, avoid re-dosing until you know what to expect.

    If you think someone has overdosed, call ‘000’ immediately.

    It’s best to test! Only a very small amount is needed – approximately 10mg (0.01g)
    Free, Legal & Confidential
    The Victorian Pill Testing service
    95 Brunswick Street
    Fitzroy VIC
    Call: 1800 762 844
    www.vicpilltesting.org.au

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