What the FDA labels say about taking them together
Methylene blue and nortriptyline
Nortriptyline's FDA label of December 4, 2024 names methylene blue in its contraindications section; the methylene blue label PlainMeds reads does not name nortriptyline. The nortriptyline label: “Starting Pamelor in a patient who is being treated with MAOIs such as linezolid or intravenous methylene blue is also contraindicated because of an increased risk of serotonin syndrome.”
Check it at the source: the methylene blue FDA label on DailyMed (effective May 28, 2025, American Regent, Inc.); the nortriptyline FDA label on DailyMed (effective December 4, 2024).
What does the methylene blue label say about nortriptyline?
Methylene blue's label (effective May 28, 2025) does not name nortriptyline in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (PROVAYBLUE), NDA204630 (Provepharm Sas), as published by American Regent, Inc., effective May 28, 2025 (SPL set 4f6848e5-35ed-4046-b13c-3032b5ba3232), via openFDA; the full label on DailyMed
What does the nortriptyline label say about methylene blue?
Nortriptyline label, contraindicationsStarting Pamelor in a patient who is being treated with MAOIs such as linezolid or intravenous methylene blue is also contraindicated because of an increased risk of serotonin syndrome ( see WARNINGS and DOSAGE AND ADMINISTRATION ).
Nortriptyline label, warningsSerotonin Syndrome The development of a potentially life-threatening serotonin syndrome has been reported with SNRIs and SSRIs, including Pamelor, alone but particularly with concomitant use of other serotonergic drugs (including triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, tryptophan, buspirone, and St. John’s Wort) and with drugs that impair metabolism of serotonin (in particular, MAOIs, both those intended to treat psychiatric disorders and also others, such as linezolid and intravenous methylene blue).
Source: FDA drug label (PAMELOR), SpecGx LLC, effective December 4, 2024 (SPL set e17dc299-f52d-414d-ab6e-e809bd6f8acb), 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
| Methylene blue | Nortriptyline | |
|---|---|---|
| Labeled for | n/a | Depression |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | n/a | $0.113 per capsule 10 mg capsule |
| Shortage now | No current entry | 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