Methadone and Selegiline interaction
Methadone and Selegiline: 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 Methadone (METHADOSE) label · effective 2026-04-27
Serotonin Syndrome : Potentially life-threatening condition could result from concomitant serotonergic drug administration.
Serotonin Syndrome with Concomitant Use of Serotonergic Drugs Cases of serotonin syndrome, a potentially life-threatening condition, have been reported during concomitant use of METHADOSE with serotonergic drugs.
Monoamine Oxidase Inhibitors (MAOIs) Clinical Impact: MAOI interactions with opioids may manifest as serotonin syndrome or opioid toxicity (e.g., respiratory depression, coma) [see Warnings and Precautions ( 5.1 , 5.9 )] .
Intervention: The use of METHADOSE is not recommended for patients taking MAOIs or within 14 days of stopping such treatment.
Serotonergic Drugs Clinical Impact: The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome [see Warnings and Precautions ( 5.9 )] .
From the Selegiline (ZELAPAR) label · effective 2021-06-01
ZELAPAR is contraindicated in patients with: • Concomitant use of opioid drugs (e.g., meperidine, tramadol, or methadone).
ZELAPAR is contraindicated in patients using the following drugs: opioid drugs (e.g., meperidine, tramadol, methadone), MAO inhibitors including selective MAO-B inhibitors, dextromethorphan, St.
Opioid Drugs Because serious, sometimes fatal reactions have been precipitated with concomitant use of opioid drugs (e.g., meperidine and its derivatives, methadone, or tramadol) and MAOIs, including selective MAO-B inhibitors, concomitant use of these drugs with ZELAPAR is contraindicated [see Contraindications ( 4 ) and Warnings and Precautions ( 5.2 )] .
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.