The short answer
Do not combine St. John’s wort with nevirapine without the HIV prescriber’s direction. Current labeling does not recommend co-use because it may lower nevirapine concentrations and contribute to loss of viral control or resistance.
What this answer covers
Hypericum perforatum products; strength and hyperforin content vary. Immediate-release and extended-release nevirapine schedules differ.
- Supplement or preparation
- Hypericum perforatum
- Medication ingredient
- nevirapine
The current label names the herb
Nevirapine labeling specifically warns against St. John’s wort co-use because reduced nevirapine concentrations may lead to loss of virologic response and possible resistance.
This is an exposure concern, not proven malabsorption
The warning concerns reduced drug concentrations. It should not be restated as a demonstrated reduction in intestinal absorption, and the label does not provide an effect size for every herbal preparation.
A timing gap is not a substitute
A short separation does not address sustained enzyme induction. No protective hours-apart schedule is established, and an unknown low-strength preparation cannot be assumed exempt from the labeled precaution.
Coordinate starting and stopping
Contact the HIV prescriber if you are taking the herb. Keep taking prescribed antiretroviral treatment unless the clinician directs otherwise, and do not compensate by changing nevirapine’s dose yourself.
Evidence and practical considerations
Absorption & effectiveness
Exact current immediate-release/extended-release labels name St John’s wort and do not recommend co-use owing to lower exposure/virologic risk. Supports exposure and avoidance, not proven reduced intestinal absorption or a protective interval.
- Exact scope
- Hypericum perforatum products; strength and hyperforin content vary. Immediate-release and extended-release nevirapine schedules differ. with Nevirapine immediate-release oral tablets; extended-release formulation considered separately.
- Medication form and route
- oral medication; oral supplement
What remains uncertain
- No unmeasured pair incidence, blanket class transfer or arbitrary spacing interval.
Factors that may matter: Preparation; Dose; Other medicines; Organ function.
Read the supporting source summaries
Source 1: current product label
dailymed.nlm.nih.gov · Source check Sep 11, 2026
Population: People prescribed nevirapine
Serious hepatic and skin reactions; metabolism through CYP3A and CYP2B6 with autoinduction. St John’s wort co-use not recommended because of reduced exposure/virologic risk.
How this applies: Exact nevirapine RxCUI 53654 IN, with stated salt/formulation/route bridge.
Exact route and formulation apply. Label precautions do not quantify untested botanical pairs or support arbitrary supplement doses.
Source 2: current product label
dailymed.nlm.nih.gov · Source check Sep 11, 2026
Population: People prescribed nevirapine
Shares CYP3A/CYP2B6 metabolism, autoinduction and serious liver/skin precautions. Different release/dosing formulation.
How this applies: Exact nevirapine RxCUI 53654 IN, with stated salt/formulation/route bridge.
Immediate-release and extended-release schedules are not interchangeable without the prescribed transition plan.
Research assessment: · Open full citations ↗
Timing & monitoring
Exact current immediate-release/extended-release labels name St John’s wort and do not recommend co-use owing to lower exposure/virologic risk. Supports exposure and avoidance, not proven reduced intestinal absorption or a protective interval.
- Exact scope
- Hypericum perforatum products; strength and hyperforin content vary. Immediate-release and extended-release nevirapine schedules differ. with Nevirapine immediate-release oral tablets; extended-release formulation considered separately.
- Medication form and route
- oral medication; oral supplement
What remains uncertain
- No unmeasured pair incidence, blanket class transfer or arbitrary spacing interval.
Factors that may matter: Preparation; Dose; Other medicines; Organ function.
Read the supporting source summaries
Source 1: current product label
dailymed.nlm.nih.gov · Source check Sep 11, 2026
Population: People prescribed nevirapine
Serious hepatic and skin reactions; metabolism through CYP3A and CYP2B6 with autoinduction. St John’s wort co-use not recommended because of reduced exposure/virologic risk.
How this applies: Exact nevirapine RxCUI 53654 IN, with stated salt/formulation/route bridge.
Exact route and formulation apply. Label precautions do not quantify untested botanical pairs or support arbitrary supplement doses.
Source 2: current product label
dailymed.nlm.nih.gov · Source check Sep 11, 2026
Population: People prescribed nevirapine
Shares CYP3A/CYP2B6 metabolism, autoinduction and serious liver/skin precautions. Different release/dosing formulation.
How this applies: Exact nevirapine RxCUI 53654 IN, with stated salt/formulation/route bridge.
Immediate-release and extended-release schedules are not interchangeable without the prescribed transition plan.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Research summary published | |
| Article prepared | |
| Prepared exact nevirapine article with formulation-specific evidence and uncertainty. |
Article revision: 2cafb3e481ea2a5f
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.