What term describes the use of plants and plant materials for their healing or rejuvenating properties?

Closely related to herbalism, phytotherapy is the intended medical use of plants and plant extracts for therapeutic purposes. A possible differentiation with herbalism is that phytotherapy may require constituents in the plant extract be standardized by adhering to a minimum content of one or several active compounds in the therapeutic product.

Modern phytotherapy may use conventional methods to assess herbal drug quality, but more typically relies on modern processes like high-performance liquid chromatography (HPLC), gas chromatography, ultraviolet/visible spectrophotometry or atomic absorption spectroscopy to identify species, measure bacteriological contamination, assess potency, and create Certificates of Analysis for the material.

Phytotherapy is distinct from homeopathy and anthroposophic medicine, and avoids mixing plant and synthetic bioactive substances. Phytotherapy is regarded by some as traditional medicine.