Ketamine and Sodium oxybate interaction
Ketamine and Sodium oxybate: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Ketamine (Ketalar) label · effective 2026-03-27
Benzodiazepines, Opioid Analgesics, or other CNS Depressants : Concomitant use may result in profound sedation, respiratory depression, coma, or death.
Benzodiazepines, Opioid Analgesics, or Other CNS Depressants Concomitant use of ketamine with opioid analgesics, benzodiazepines, or other central nervous system (CNS) depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death [see Drug Interactions ( 7.3 )] .
Closely monitor neurological status and respiratory parameters, including respiratory rate and pulse oximetry, when KETALR and opioid analgesics, benzodiazepines, or other CNS depressants are co-administered.
Benzodiazepines, Opioid Analgesics, Or Other CNS Depressants Concomitant use of ketamine with opioid analgesics, benzodiazepines, or other central nervous system (CNS) depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death [see Warnings and Precautions ( 5.9 )] .
From the Sodium oxybate (Xyrem) label · effective 2025-07-01
• Central Nervous System Depression Xyrem (sodium oxybate) is a CNS depressant.
Abuse or misuse of illicit GHB, either alone or in combination with other CNS depressants, is associated with CNS adverse reactions, including seizure, respiratory depression, decreases in the level of consciousness, coma, and death [see Warnings and Precautions ( 5.2 )].
Central Nervous System Depression • Xyrem is a CNS depressant, and respiratory depression can occur with Xyrem use ( 5.1 , 5.4 )
…concurrent use of Xyrem with other CNS depressants, including but not limited to opioid analgesics, benzodiazepines, sedating antidepressants or antipsychotics, sedating anti-epileptic drugs, general anesthetics, muscle relaxants, and/or illicit CNS depressants, may increase the risk of respiratory depression, hypotension, profound sedation, syncope, and death.
Abuse of illicit GHB, either alone or in combination with other CNS depressants, is associated with CNS adverse reactions, including seizure, respiratory depression, decreases in the level of consciousness, coma, and death.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.