Suspected adverse reactions to medications and food supplements containing Serenoa repens: A worldwide analysis of pharmacovigilance and phytovigilance spontaneous reports

The safety of Serenoa repens (SR)-containing products was evaluated conducting a retrospective worldwide analysis of pharmaco- and phytovigilance report forms of suspected adverse reactions (SARs) collected up to 31 January 2022. Multivariate logistic regression was performed to estimate the odds ratios (ORs) of serious SAR. A total of 1810 report forms were analysed; 92% of subjects were males, with a median age of 69 years; 44% of cases were defined as serious. Subjects exposed to dietary supplements had a higher risk of developing serious SARs (OR: 1.60 [95% CI: 1.20-2.15]), as subjects exposed to 2-5 (OR: 1. 83 [95% CI: 1.30-2.58]) or more than 5 (OR: 3.45 [95% CI: 2.36-5.06]) suspect/interacting products. The probability of experiencing serious SAR was higher for subjects exposed to concomitant products (OR: 1.55 [95% CI: 1.15-2.08]), to more than four active compounds (OR: 4.38 [95% CI: 3.21-5.99]) and to SR for more than 14 days (OR: 1.89 [95% CI: 1.10-3, 22]), and lower for subjects exposed to higher doses of SR (OR: of 0.34 [95% CI: 0.20-0.58]). This evidence improves awareness on safety of SR containing products, suggesting the need of a further update of periodic reviews by national and international regulatory agencies.