Cocaine and Phenelzine interaction
Cocaine and Phenelzine: 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 Phenelzine (phenelzine sulfate) label · effective 2026-05-21
Therefore, patients being treated with phenelzine sulfate should not take sympathomimetic drugs (including amphetamines, cocaine, methylphenidate, dopamine, epinephrine, and norepinephrine) or related compounds (including methyldopa, L-dopa, L-tryptophan, L-tyrosine, and phenylalanine).
Also, they should not be given cocaine or local anesthesia containing sympathomimetic vasoconstrictors.
From the Cocaine (NUMBRINO) label · effective 2026-01-12
Sympathomimetics, postganglionic blocking agents, and tricyclic antidepressants: Concomitant administration may increase the risk of cardiovascular adverse reactions.
Monoamine-oxidase inhibitors: Concomitant administration may potentiate the effects and toxicity of monoamine-oxidase inhibitors.
Plasma cholinesterase activity may be decreased by chronic administration of certain monoamine oxidase inhibitors, oral contraceptives, glucocorticoids, antimyasthenics (neostigmine), cyclophosphamide, and possibly thiotepa.
Tricyclic Antidepressants Tricyclic antidepressants may increase the activity of the sympathetic nervous system, which may also be increased by administration of cocaine hydrochloride.
Monoamine-Oxidase Inhibitors Cocaine hydrochloride may potentiate the effects and toxicity of MAO inhibitors.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
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.