Does Duloxetine Interact With Fluoxetine?
Similar effects would be expected with other potent CYP2D6 inhibitors (e.g., fluoxetine, quinidine) [see Warnings and Precautions (5.12) ].
Severity: Moderate
Severity basis: drug interactions section (keywords: caution). Combining Duloxetine (SNRI antidepressant) and Fluoxetine (SSRI antidepressant) is classified as a moderate interaction.
What to Do
Use this combination with caution. Your prescriber may monitor you more closely or adjust doses.
How This Interaction Works
Interactions like this one can happen when two medicines have overlapping effects, or when one changes how the other is absorbed, broken down, or cleared from the body. Duloxetine is a snri antidepressant and Fluoxetine is a ssri antidepressant; together they are documented as a moderate interaction. How much this matters depends on your dose, your other medications, and your overall health.
If You Take Both Medications
If you have been prescribed both Duloxetine and Fluoxetine, do not start, stop, or change either medication on your own — some medicines are unsafe to stop suddenly. Tell your prescriber and pharmacist that you take both so they can decide whether the combination is right for you, adjust the dose, monitor you more closely, or suggest an alternative.
From the FDA Label
Similar effects would be expected with other potent CYP2D6 inhibitors (e.g., fluoxetine, quinidine) [see Warnings and Precautions (5.12) ].
Source: FDA structured product labeling (set_id 00628e5e-4c5b-2573-e063-6294a90a0e3b).
Check these against your full medication list in our free Interaction Checker
Frequently Asked Questions
Can you take Duloxetine and Fluoxetine together?
Duloxetine and Fluoxetine have a documented moderate interaction. Use this combination with caution. Your prescriber may monitor you more closely or adjust doses.
How serious is the Duloxetine and Fluoxetine interaction?
It is classified as a moderate interaction, based on the FDA label's drug interactions section (keywords: caution). A moderate interaction can be clinically meaningful and usually calls for monitoring or a dose adjustment.
What should I do if I'm taking both Duloxetine and Fluoxetine?
If you have been prescribed both Duloxetine and Fluoxetine, do not start, stop, or change either medication on your own — some medicines are unsafe to stop suddenly. Tell your prescriber and pharmacist that you take both so they can decide whether the combination is right for you, adjust the dose, monitor you more closely, or suggest an alternative.
This information is educational — not medical advice.
This page is provided for general educational purposes and summarizes publicly available data from sources such as the U.S. Food & Drug Administration. It is not a substitute for the judgment of a licensed clinician and should not be used to start, stop, or change any medication. It may be incomplete or out of date, and individual circumstances vary. Always talk with your prescriber or pharmacist about your specific medications and health conditions. If you think you may have a medical emergency, call 911.
Other Duloxetine Interactions
- Duloxetine + Amitriptyline(moderate)
- Duloxetine + Ciprofloxacin(moderate)
- Duloxetine + Nortriptyline(moderate)
- Duloxetine + Aspirin(minor)
- Duloxetine + Buspirone(minor)
- Duloxetine + Famotidine(minor)
- Duloxetine + Lithium(minor)
- Duloxetine + Lorazepam(minor)
- Duloxetine + Paroxetine(minor)
- Duloxetine + Temazepam(minor)
- Duloxetine + Tramadol(minor)
- Duloxetine + Warfarin(minor)
Other Fluoxetine Interactions
- Fluoxetine + Olanzapine(contraindicated)
- Fluoxetine + Aspirin(major)
- Fluoxetine + Warfarin(major)
- Fluoxetine + Alprazolam(moderate)
- Fluoxetine + Aripiprazole(moderate)
- Fluoxetine + Atomoxetine(moderate)
- Fluoxetine + Buspirone(moderate)
- Fluoxetine + Carbamazepine(moderate)
- Fluoxetine + Diazepam(moderate)
- Fluoxetine + Glimepiride(moderate)
- Fluoxetine + Insulin Aspart(moderate)
- Fluoxetine + Insulin Glargine(moderate)
- Fluoxetine + Lithium(moderate)
- Fluoxetine + Phenytoin(moderate)
- Fluoxetine + Tramadol(moderate)
- Fluoxetine + Amiodarone(minor)
- Fluoxetine + Amitriptyline(minor)
- Fluoxetine + Bupropion(minor)
- Fluoxetine + Carvedilol(minor)
- Fluoxetine + Clonazepam(minor)
- Fluoxetine + Codeine(minor)
- Fluoxetine + Ketoconazole(minor)
- Fluoxetine + Metoprolol(minor)
- Fluoxetine + Risperidone(minor)
- Fluoxetine + Sertraline(minor)
- Fluoxetine + Tacrolimus(minor)
- Fluoxetine + Venlafaxine(minor)
- Fluoxetine + Zolpidem(minor)