Case reports have established carisoprodol as a drug of abuse, but no systematic studies have been published about the extent of abuse.

It is suggested that abuse and dependence potential of carisoprodol are due to carisoprodol’s metabolite meprobamate (federally controlled substance) 6 Carisoprodol undergoes hepatic biotransformation to three primary metabolites: hydroxycarisoprodol, hydroxymeprobamate, and meprobamate. The significant serum levels of meprobamate after chronic use of carisoprodol may lead to meprobarnate dependency. Withdrawal from meprobamate may result in severe reactions including seizures and coma.

One study evaluated abuse risk in patients taking carisoprodol. This study enrolled 40 patients taking carisoprodol for more than 3 months. It assessed the potential for abuse using an unvalidated six-item questionnaire and found that 20% of patients with no history of substance abuse and 65% with a history of substance abuse responded yes to one or more questions, which the authors suggested indicated a tendency towards possible abuse.

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