Methyldopa and Phenelzine interaction
Methyldopa 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 Methyldopa label · effective 2025-03-28
CONTRAINDICATIONS Methyldopa is contraindicated in patients: – with active hepatic disease, such as acute hepatitis and active cirrhosis. – with liver disorders previously associated with methyldopa therapy (see WARNINGS ). – with hypersensitivity to any component of this product. – on therapy with monoamine oxidase (MAO) inhibitors.
Monoamine oxidase (MAO) inhibitors: See CONTRAINDICATIONS .
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).
…hydrochloride desipramine hydrochloride imipramine hydrochloride doxepin carbamazepine cyclobenzaprine HCl amoxapine maprotiline HCl trimipramine maleate protriptyline HCl mirtazapine Phenelzine sulfate should be used with caution in combination with antihypertensive drugs, including thiazide diuretics and β-blockers, since exaggerated hypotensive effects may result.
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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.