Fosamprenavir and Venlafaxine interaction
Fosamprenavir and Venlafaxine: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Fosamprenavir (Fosamprenavir Calcium) label · effective 2026-06-30
Antidepressant: Paroxetine, trazodone ↓ Paroxetine Any paroxetine dose adjustment should be guided by clinical effect (tolerability and efficacy). ↑ Trazodone Adverse events of nausea, dizziness, hypotension, and syncope have been observed following coadministration of trazodone and ritonavir.
Tricyclic antidepressants: Amitriptyline, imipramine ↑ Tricyclics Therapeutic concentration monitoring is recommended for tricyclic antidepressants. a See Clinical Pharmacology (12.3)
From the Venlafaxine (Venlafaxine Hydrochloride) label · effective 2025-01-31
Concomitant use of CYP3A4 inhibitors and venlafaxine may increase levels of venlafaxine and ODV.
Therefore, caution is advised if a patient’s therapy includes a CYP3A4 inhibitor and venlafaxine concomitantly.
CYP3A4 Venlafaxine did not inhibit CYP3A4 in vitro .
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.