Fluoxetine and Venlafaxine interaction

Fluoxetine and Venlafaxine: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.

Major

Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.

What the FDA labels say

From the Fluoxetine (Prozac) label · effective 2026-01-08

Major

If concomitant use of PROZAC with other serotonergic drugs is clinically warranted, patients should be made aware of a potential increased risk for serotonin syndrome, particularly during treatment initiation and dose increases ( 5.2 )

Warnings and precautionsby drug classView label on DailyMed
Major

If concomitant use of PROZAC with other serotonergic drugs is clinically warranted, inform patients of the increased risk for serotonin syndrome and monitor for symptoms.

Warnings and precautionsby drug classView label on DailyMed
Major

Bleeding reactions related to SNRIs and SSRIs use have ranged from ecchymoses, hematomas, epistaxis, and petechiae to life-threatening hemorrhages.

Warnings and precautionsby drug classView label on DailyMed
Major

If serotonin syndrome occurs, consider discontinuation of PROZAC and/or concomitant serotonergic drugs [see Warnings and Precautions ( 5.2 )] .

Drug interactionsby drug classView label on DailyMed
Moderate

The risk is increased with concomitant use of other serotonergic drugs (including triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, tryptophan, meperidine, methadone, buspirone, amphetamines, and St.

Warnings and precautionsby drug classView label on DailyMed

From the Venlafaxine (Venlafaxine Hydrochloride) label · effective 2025-01-31

Major

Anyone considering the use of Venlafaxine Extended Release Tablets or any other antidepressant in a child, adolescent, or young adult must balance this risk with the clinical need.

Boxed warningby drug classView label on DailyMed
Major

If concomitant use of Venlafaxine Extended Release Tablets with other serotonergic drugs is clinically warranted, patients should be made aware of a potential increased risk for serotonin syndrome, particularly during treatment initiation and dose increases.

Warnings and precautionsby drug classView label on DailyMed
Major

If concomitant use of Venlafaxine Extended Release Tablets with other serotonergic drugs is clinically warranted, inform patients of the increased risk for serotonin syndrome and monitor for symptoms.

Warnings and precautionsby drug classView label on DailyMed
Major

Bleeding events related to SSRIs and SNRIs use have ranged from ecchymoses, hematomas, epistaxis, and petechiae to life-threatening hemorrhages.

Warnings and precautionsby drug classView label on DailyMed
Major

If serotonin syndrome occurs, consider discontinuation of Venlafaxine Extended Release Tablets and/or concomitant serotonergic drugs [see Warning and Precautions ( 5.2 )].

Drug interactionsby drug classView label on DailyMed

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Not 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.