Herbalism (also herbal medicine or phytotherapy) is the study of botany and use of plants intended for medicinal purposes or for supplementing a diet. Plants have been the basis for medical treatments through much of human history, and such traditional medicine is still widely practiced today. Modern medicine recognizes herbalism as a form of alternative medicine and pseudoscience, as the practice of herbalism is not strictly based on evidence gathered using the scientific method. Modern medicine makes use of many plant-derived compounds as the basis for evidence-based pharmaceutical drugs. Although phytotherapy may apply modern standards of effectiveness testing to herbs and medicines derived from natural sources, few high-quality clinical trials and standards for purity or dosage exist. The scope of herbal medicine is sometimes extended to include fungal and bee products, as well as minerals, shells and certain animal parts.
The term, phytomedicine, may also refer to the science of pathology and damage to plants, the causes thereof, their manifestations, development, dissemination, methods for maintaining plant health, and measures used to control plant diseases and their causes.
As terms referring to medicinal or dietary practices of using botanical products, herbalism, herbal medicine or phytotherapy are used interchangeably in many countries, including Canada, Norway, the United Kingdom, other countries in Europe and South America, South Africa, and the United States.
General practices include ancient methods of traditional Chinese medicine and Ayurveda. Practitioners of herbalism or phytotherapy are referred to as herbalists or phytotherapists. Products used in herbalism may be called herbal medicines, botanicals, natural health products, herbal remedies, herbal supplements, or phytotherapies.