Does Genvoya Interact with Common Herbal Supplements?
Genvoya, a fixed-dose combination of elvitegravir, cobicistat, emtricitabine, and tenofovir alafenamide used for HIV treatment, interacts with several common herbal supplements. Cobicistat, a CYP3A inhibitor in Genvoya, boosts drug levels but heightens risks with herbs that induce or inhibit CYP3A or affect renal function. Key interactions stem from official labeling and clinical pharmacology data.[1][2]
St. John's Wort and Genvoya
St. John's wort strongly induces CYP3A, reducing elvitegravir levels by up to 76% and risking treatment failure or resistance. Avoid completely—Genvoya prescribing information contraindicates it.[1]
Garlic Supplements with Genvoya
Garlic induces CYP3A and may lower elvitegravir exposure, though evidence is less robust than St. John's wort. Use caution; monitor viral load if combined.[2][3]
Ginseng and Genvoya Risks
Asian ginseng (Panax ginseng) weakly induces CYP3A and may decrease elvitegravir efficacy. Limited data exists, but avoidance is recommended during Genvoya use.[3]
Milk Thistle or Silymarin Interactions
Milk thistle inhibits CYP3A mildly, potentially raising elvitegravir and cobicistat levels, which could increase toxicity risks like renal issues. Space doses or avoid.[2]
Ginkgo Biloba Effects on Genvoya
Ginkgo induces CYP3A modestly, possibly reducing Genvoya efficacy. No strong clinical trials, but herbal guides advise against concurrent use.[3]
Turmeric or Curcumin Concerns
High-dose turmeric inhibits CYP3A and P-gp, elevating Genvoya components and risking side effects like nausea or kidney strain. Culinary amounts are likely safe; supplements warrant caution.[2]
What About Echinacea, Saw Palmetto, or Valerian?
- Echinacea: Weak CYP3A inducer; low interaction risk but monitor.
- Saw palmetto: Minimal CYP impact; generally safe.
- Valerian: No significant interaction reported.[3]
Patients should inform providers of all supplements. Drug interaction checkers like Liverpool HIV Drug Interactions confirm these via CYP3A pathways.[4]
When to Check for Interactions
Always use tools like the University of Liverpool checker or consult a pharmacist before starting herbs. Genvoya's renal and hepatic effects amplify risks with supplements affecting those organs.[1][4]
Sources
[1]: Genvoya Prescribing Information (Gilead)
[2]: NIH HIV Drug Interactions
[3]: Natural Medicines Database
[4]: Liverpool HIV Drug Interactions Checker