Herbal medicine may also refer to phytomedicine phytotherapy paraherbalism which are alternative and pseudoscientific practices of using unrefined plant or animal extracts as supposed medicines or health-promoting agents. Phytotherapy differs from plant-derived medicines in standard pharmacology because it does not isolate or standardize biologically active compounds but rather relies on the false belief that preserving various substances from a given source with less processing is safer or more effective — for which there is no evidence. Herbal dietary supplements most often fall under the phytotherapy category.