What the FDA labels say about taking them together
Duloxetine and methadone
Duloxetine's FDA label of May 14, 2024 names methadone in its warnings and precautions section; methadone's label does not name duloxetine itself but warns about its class (SNRIs (serotonin and norepinephrine reuptake inhibitors)). The duloxetine label: “The risk is increased with concomitant use of other serotonergic drugs and with drugs that impair metabolism of serotonin.”
Check it at the source: the duloxetine FDA label on DailyMed (effective May 14, 2024, SUN PHARMACEUTICAL INDUSTRIES, INC.); the methadone FDA label on DailyMed (effective December 8, 2025, Epic Pharma, LLC).
What does the duloxetine label say about methadone?
Duloxetine label, warnings and precautionsThe risk is increased with concomitant use of other serotonergic drugs (including triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, meperidine, methadone, tryptophan, buspirone, amphetamines, and St. John’s Wort) and with drugs that impair metabolism of serotonin [see Contraindications (4), Drug Interactions (7)].
Source: FDA drug label (Duloxetine, NDA219131), Almatica Pharma LLC, effective March 2, 2026 (SPL set bb2ca3bf-983c-1e4a-a91d-dc7dee66d741), via openFDA
Source: FDA drug label (DRIZALMA SPRINKLE), SUN PHARMACEUTICAL INDUSTRIES, INC., effective May 14, 2024 (SPL set b41423b8-dfec-4d79-ba3c-e43a87803d85), via openFDA; the full label on DailyMed
What does the methadone label say about duloxetine?
Methadone's label does not name duloxetine itself; it warns about its class (SNRIs (serotonin and norepinephrine reuptake inhibitors)):
Methadone label, warnings and precautionsSyndrome with Concomitant Use of Serotonergic Drugs Cases of serotonin syndrome, a potentially life-threatening condition, have been reported during concomitant use of methadone hydrochloride tablets with serotonergic drugs. Serotonergic drugs include selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), triptans, 5-HT3 receptor antagonists, drugs that affect the serotonergic neurotransmitter system (e.g., mirtazapine …
Methadone label, warnings and precautionsSyndrome with Concomitant Use of Serotonergic Drugs Cases of serotonin syndrome, a potentially life-threatening condition, have been reported during concomitant use of DISKETS with serotonergic drugs. Serotonergic drugs include selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), triptans, 5-HT3 receptor antagonists, drugs that affect the serotonergic neurotransmitter system (e.g., mirtazapine, trazodone, tramadol), certain …
Source: FDA drug label (Methadone Hydrochloride), Epic Pharma, LLC, effective December 8, 2025 (SPL set 6da7501b-b881-4bc7-891a-74214a00a3ac), 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
| Duloxetine | Methadone | |
|---|---|---|
| Labeled for | Depression, Anxiety, Nerve pain and fibromyalgia, Pain | Pain, Opioid use disorder |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.102 per capsule 30 mg capsule | $0.177 per tablet 10 mg tablet |
| 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