Amitriptyline and Duloxetine interaction
Amitriptyline and Duloxetine: 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 Amitriptyline (Amitriptyline Hydrochloride) label · effective 2025-11-25
Anyone considering the use of amitriptyline hydrochloride tablets or any other antidepressant in a child, adolescent, or young adult must balance this risk with the clinical need.
The drugs that inhibit cytochrome P450 2D6 include some that are not metabolized by the enzyme (quinidine; cimetidine) and many that are substrates for P450 2D6 (many other antidepressants, phenothiazines, and the Type 1C antiarrhythmics propafenone and flecainide).
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.
If serotonin syndrome occurs, consider discontinuation of CYMBALTA and/or concomitant serotonergic drugs [see Warnings and Precautions ( 5.4 )] .
The risk is increased with concomitant use of other serotonergic drugs (including triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, meperidine, methadone, tryptophan, buspirone, amphetamines, and St.
…Metabolized by CYP2D6 — Co-administration of CYMBALTA with drugs that are extensively metabolized by CYP2D6 and that have a narrow therapeutic index, including certain antidepressants (tricyclic antidepressants [TCAs], such as nortriptyline, amitriptyline, and imipramine), phenothiazines and Type 1C antiarrhythmics (e.g., propafenone, flecainide), should be approached…
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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.