INTRODUCTION: Sildenafil belongs to the class of drugs called phosphodiesterase 5 inhibitors. It is used in the treatment of erectile dysfunction and pulmonary arterial hypertension. Sildenafil is metabolized predominantly by CYP3A4 and, to a lesser extent, by CYP2C9. Thus, it may be involved in pharmacokinetic interactions when co-administered with other substrates of these enzymes.
AIM: The current study aimed to review the reported herb-drug interactions between sildenafil and concomitantly used herbs, foods, and beverages.
MATERIALS AND METHODS: A thorough review of scientific databases such as Web of Science, Scopus, PubMed, and ResearchGate was conducted.
RESULTS AND DISCUSSION: Overall, relatively few studies are found on potential interactions between sildenafil and natural products. Some authors reported pharmacokinetic interactions in vivo when sildenafil is taken simultaneously with herbal extracts, foods, and beverages. As a result, either an increase or a decrease in oral bioavailability of sildenafil was observed.
CONCLUSION: Although sildenafil is relatively safe when taken under medical prescription, its administration may be potentially dangerous when used concomitantly with other drugs or nutritional supplements, as well as with some foods and beverages, especially without medical advice. The occurrence of interactions may lead to adverse drug reactions or therapy failure. Therefore, simultaneous intake of sildenafil with herbal extracts as well as certain foods is not recommended until more data about its safety is available.
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