What the FDA labels say about taking them together
Doxepin and fluoxetine
Doxepin's FDA label (Prudoxin) of June 29, 2017 names fluoxetine in its drug interactions section; fluoxetine's label does not name doxepin itself but warns about its class (Tricyclic antidepressants). The doxepin label: “While all the selective serotonin reuptake inhibitors (SSRIs), e.g., fluoxetine, sertraline, and paroxetine, inhibit P450 2D6, they may vary in the extent of inhibition.”
Check it at the source: the doxepin FDA label on DailyMed (effective December 30, 2025, Leading Pharma, LLC); the fluoxetine FDA label on DailyMed (effective January 8, 2026, Dista Products Company).
What does the doxepin label say about fluoxetine?
Prudoxin label (Mylan Pharmaceuticals Inc., June 29, 2017), drug interactionsWhile all the selective serotonin reuptake inhibitors (SSRIs), e.g., fluoxetine, sertraline, and paroxetine, inhibit P450 2D6, they may vary in the extent of inhibition.
Source: FDA drug label (Prudoxin, NDA020126), Mylan Pharmaceuticals Inc., effective June 29, 2017 (SPL set ca53346b-8ab3-4722-98f6-cf272706d3fa), via openFDA
Source: FDA drug label (DOXEPIN HYDROCHLORIDE), Leading Pharma, LLC, effective December 30, 2025 (SPL set e6a4cb10-1928-4abe-8797-404c9ddc37dd), via openFDA; the full label on DailyMed
What does the fluoxetine label say about doxepin?
Fluoxetine's label does not name doxepin itself; it warns about its class (Tricyclic antidepressants):
Fluoxetine label, drug interactionsThe concomitant use of serotonergic drugs (including other SSRIs, SNRIs, triptans, tricyclic antidepressants, opioids, lithium, buspirone, amphetamines, tryptophan, and St. John's Wort) with PROZAC increases the risk of serotonin syndrome.
Fluoxetine label, warnings and precautionsThe risk is increased with concomitant use of other serotonergic drugs (including triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, tryptophan, meperidine, methadone, buspirone, amphetamines, and St. John's Wort) and with drugs that impair metabolism of serotonin, i.e., MAOIs [see Contraindications ( 4 ), Drug Interactions ( 7.1 )].
Source: FDA drug label (Prozac), NDA018936 (Eli Lilly And Co), as published by Dista Products Company, effective January 8, 2026 (SPL set c88f33ed-6dfb-4c5e-bc01-d8e36dd97299), 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
| Doxepin | Fluoxetine | |
|---|---|---|
| Labeled for | Depression, Anxiety, Eczema (atopic dermatitis), Insomnia | Depression, Anxiety, Bipolar disorder |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.0779 per capsule 10 mg capsule | $0.0519 per capsule 40 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