Traditional medicine and medicinal plants: historical background, scientific evidence, and integration into clinical practice in Brazil

Abstract

Traditional and complementary medicine (TCM), particularly the use of medicinal plants, remains a relevant component of health systems in many regions of the world, especially in settings marked by strong cultural traditions and unequal access to biomedical care. Recognized by the World Health Organization, TCM encompasses knowledge and practices grounded in diverse cultural experiences and calls for safe, regulated, and evidence-based integration. The therapeutic use of plants has accompanied humanity since Antiquity, with records in Eastern, European, and Indigenous medical systems, and has been continuously shaped by cultural and scientific exchanges. In Brazil, traditional herbal medicine arises from the interaction of Indigenous, African, and European knowledge systems, reflected in the practices of Indigenous peoples, traditional communities, and popular healers such as herbalists and faith healers. Ethnobotanical and pharmacological studies indicate the therapeutic potential of many species, although robust clinical trials remain limited. Challenges related to safety, standardization, and rational use persist, particularly in informal markets. Public health policies within Brazil’s Unified Health System formally recognize phytotherapy and establish criteria for its qualified use, underscoring the need for basic training of health professionals.