Boswellia: A Systematic Review of the Adverse Events

Boswellia is one of the oldest alternative medicinal plants in the world. Boswellia is thought to have anti-inflammatory effects, antioxidant properties, and immunity stimulating. This herbal medicine relieves several diseases such as osteoarthritis, asthma, and inflammatory bowel diseases. Little is known about the adverse drug reactions of Boswellia; this systematic review attempted to identify the potential side effects of this supplement and its severity in different diseases. Relevant studies conducted up to May 2024 were identified from Scopus, Science Direct, Web of Science, PubMed, Cochrane Library, and Embase databases. Spontaneous reports about the side effects of Boswellia were gathered from three international spontaneous reporting schemes, as well. Age, sex, type of disease, dosage, and duration of the drug as well as self-reported side effects were considered. Subgroup analysis was performed to determine the prevalence of each adverse effect of Boswellia. The quality of the included trials was assessed using version 2 of the Cochrane risk-of-bias tool (RoB 2). Sixty-two clinical trials were included in this review. Twenty-five of them reported side effects. Twenty-seven studies reported that Boswellia had no adverse effects, and 10 articles had not mentioned the side effects. Low-to-high risk of bias was found in clinical trials. Ten case reports were included in this study, but no case series was included. Spontaneous reporting schemes included 26 reports. The most common adverse effects were gastrointestinal disorders and cutaneous allergic reactions. Although most detected adverse effects were mild to moderate, two patients developed hypersensitivity pneumonitis and bezoar formation, respectively. This systematic study reported that Boswellia, as an herbal medicine, is often considered safe to use; however, it is possible to experience severe side effects. We suggest that Boswellia should be administered only under the supervision of a specialist doctor in usual medical treatment.