Duloxetine and Paroxetine interaction
Duloxetine and Paroxetine: 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 Duloxetine (Cymbalta) label · effective 2025-07-21
Serotonin Syndrome : Increased risk when co-administered with other serotonergic agents, but also when taken alone.
If concomitant use of CYMBALTA with other serotonergic drugs is clinically warranted, inform patients of the increased risk for serotonin syndrome and monitor for symptoms.
Other bleeding events related to SSRI and SNRI use have ranged from ecchymoses, hematomas, epistaxis, and petechiae to life-threatening hemorrhages.
If serotonin syndrome occurs, consider discontinuation of CYMBALTA and/or concomitant serotonergic drugs [see Warnings and Precautions ( 5.4 )] .
Inhibitors of CYP2D6 Concomitant use of CYMBALTA (40 mg once daily) with paroxetine (20 mg once daily) increased the concentration of duloxetine AUC by about 60%, and greater degrees of inhibition are expected with higher doses of paroxetine.
From the Paroxetine (BRISDELLE) label · effective 2025-04-28
Serotonin Syndrome: BRISDELLE can cause serotonin syndrome with increased risk when co-administered with other serotonergic agents, but also when taken alone.
If concomitant use of BRISDELLE with other serotonergic drugs (besides MAOIs) is clinically warranted, consider the increased risk of serotonin syndrome and carefully observe the patient, particularly during BRISDELLE initiation [see Contraindications ( 4.1 )
The risk is increased with concomitant use of other serotonergic agents (including triptans, tricyclic antidepressants, fentanyl, tramadol, meperidine, methadone, lithium, tryptophan, buspirone, amphetamines, and St.
Cimetidine Increased plasma concentration of paroxetine Use caution if BRISDELLE is used concomitantly with other drugs that inhibit CYP2D6 (e.g., quinidine).
If it occurs, discontinue BRISDELLE and serotonergic agents and initiate supportive measures ( 5.2 , 7.3 ).
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.