St. John's Wort - Emtriva (Emtricitabine) Interaction
Herbal: St. John's Wort
Also Known As: Hypericum perforatum, Amber Touch-and-Heal, Barbe de Saint-Jean, Chasse-diable, Demon Chaser, Fuga Daemonum, Hardhay, Herbe Aux Mille Vertus, Hypereikon, Hyperici Herba, Hypericum, Millepertuis, Perforate St. John's Wort, Racecourse Weed, Rosin Rose, Saynt Johannes Wort
Drug: Emtricitabine
Brand names:
Emtriva

Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
Jun 15, 2025
Interaction Details
Emtricitabine is classified as belonging to the following category: Non-Nucleoside Reverse Transcriptase Inhibitors (Nnrtis)
St. John's wort decreases the levels and clinical effects of NNRTIs.
St. John's wort increases the oral clearance of nevirapine (Viramune) by 35%. Subtherapeutic concentrations are associated with therapeutic failure, development of viral resistance, and development of drug class resistance. St. John's wort induces intestinal and hepatic cytochrome P450 3A4 (CYP3A4) and intestinal P-glycoprotein/MDR-1, a drug transporter.
Interaction Rating
Likelihood of Occurrence
LikelyWell-controlled human studies have demonstrated the likely existence of this interaction
References
- Piscitelli SC, Burstein AH, Chaitt D, et al. Indinavir concentrations and St John's wort. Lancet 2000;355:547-8.
- Durr D, Stieger B, Kullak-Ublick GA, et al. St. John's Wort induces intestinal P-glycoprotein/MDR1 and intestinal and hepatic CYP3A4. Clin Pharmacol Ther 2000;68:598-604.
- de Maat M, Hoetelmans R, Mathot R, et al. Drug interaction between St. John's wort and nevirapine. AIDS 2001;15:420-1.
- Soleymani S, Bahramsoltani R, Rahimi R, Abdollahi M. Clinical risks of St John's Wort (Hypericum perforatum) co-administration. Expert Opin Drug Metab Toxicol. 2017;13(10):1047-62.
St. John's Wort Overview

Emtricitabine Overview
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Emtricitabine is used along with other medications to treat human immunodeficiency virus (HIV) infection. Emtricitabine is in a class of medications called nucleoside reverse transcriptase inhibitors (NRTIs). It works by decreasing the amount of HIV in the blood. Although emtricitabine does not cure HIV, it may decrease your chance of developing acquired immunodeficiency syndrome (AIDS) and HIV-related illnesses such as serious infections or cancer. Taking these medications along with practicing safer sex and making other life-style changes may decrease the risk of transmitting (spreading) the HIV virus to other people.
St. John's Wort - More Interactions
St. John's Wort interacts with 1115 drugs
Interaction Rating Key
These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.
Major | The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur. |
Moderate | Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur. |
Minor | Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction. |
Unknown | No interactions have been reported or no interaction data is currently available. |
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
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Drug descriptions are provided by MedlinePlus.