Methamphetamine and Promethazine and dextromethorphan interaction
Methamphetamine and Promethazine and dextromethorphan: 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 Promethazine and dextromethorphan (Promethazine Hydrochloride and Dextromethorphan Hydrobromide) label · effective 2025-08-08
Epinephrine – Because of the potential for promethazine to reverse epinephrine’s vasopressor effect, epinephrine should NOT be used to treat hypotension associated with Promethazine Hydrochloride and Dextromethorphan Hydrobromide Oral Solution overdose.
From the Methamphetamine (Methamphetamine Hydrochloride) label · effective 2025-11-07
Serotonin Syndrome: Increased risk when coadministered with serotonergic agents (e.g., SSRIs, SNRIs, triptans), but also during overdosage situations.
Serotonin Syndrome Serotonin syndrome, a potentially life-threatening reaction, may occur when amphetamines are used in combination with other drugs that affect the serotonergic neurotransmitter systems such as monoamine oxidase inhibitors (MAOIs), selective serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), triptans,…
If serotonin syndrome occurs, discontinue methamphetamine hydrochloride tablets, USP and the concomitant serotonergic drug(s) [see Warnings and Precautions 5.8].
If concomitant use of methamphetamine with other serotonergic drugs or CYP2D6 inhibitors is clinically warranted, initiate methamphetamine with lower doses, monitor patients for the emergence of serotonin syndrome during drug initiation or titration, and inform patients of the increased risk for serotonin syndrome.
Serotonergic Drugs Clinical Impact: The concomitant use of amphetamines, including methamphetamine hydrochloride tablets, USP , and serotonergic drugs increases the risk of serotonin syndrome.
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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.