What the FDA labels say about taking them together
Isocarboxazid and methyldopa
Isocarboxazid's FDA label of April 21, 2026 names methyldopa in its contraindications section; the methyldopa label PlainMeds reads does not name isocarboxazid.
Check it at the source: the isocarboxazid FDA label on DailyMed (effective April 21, 2026, Lifsa Drugs LLC); the methyldopa FDA label on DailyMed (effective March 26, 2025, Chartwell RX, LLC).
What does the isocarboxazid label say about methyldopa?
Isocarboxazid label, contraindicationsUse of sympathomimetics and compounds such as guanethidine, methyldopa, methylphenidate, reserpine, epinephrine, norepinephrine, phenylalanine, dopamine, levodopa, tyrosine, and tryptophan with Marplan may precipitate hypertension, headache, and related symptoms.
Source: FDA drug label (MARPLAN), Lifsa Drugs LLC, effective April 21, 2026 (SPL set 95fde749-44ad-4668-86c4-0ff17bca0074), via openFDA; the full label on DailyMed
What does the methyldopa label say about isocarboxazid?
Methyldopa's label (effective March 26, 2025) does not name isocarboxazid in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Methyldopa), Chartwell RX, LLC, effective March 26, 2025 (SPL set e1114a58-9ab5-486e-85ed-360365b06396), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Isocarboxazid | Methyldopa | |
|---|---|---|
| Labeled for | Depression | n/a |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | n/a | n/a |
| Shortage now | In shortage | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once