Carbidopa and levodopa and Phenelzine interaction
Carbidopa and levodopa and Phenelzine: the Carbidopa and levodopa prescribing label 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 Carbidopa and levodopa (Duopa) label · effective 2026-03-19
DUOPA is contraindicated in patients who are currently taking a nonselective monoamine oxidase (MAO) inhibitor (e.g., phenelzine and tranylcypromine) or have recently (within 2 weeks) taken a nonselective MAO inhibitor.
DUOPA is contraindicated in patients taking nonselective monoamine oxidase (MAO) inhibitors ( 4 )
Monoamine Oxidase (MAO) Inhibitors The use of nonselective MAO inhibitors with DUOPA is contraindicated [see Contraindications ( 4 ) ] .
Discontinue use of any nonselective MAO inhibitors at least two weeks prior to initiating DUOPA.
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