Herbal therapy, sometimes called phytotherapy or herbal medicine, is a form of alternative medicine that has been around for centuries, with references in ancient Chinese documents and even the Christian Bible. In this form of medicine, plant seeds, berries, roots, leaves, bark, or flowers are used for medicinal purposes, either to treat or prevent ailments. Phytodrugs are mixtures of many compounds extracted from a single or many plants. These compounds are thought to display a wide scope of beneficial qualities and less undesirable side effects than more conventional drugs sold in pharmacies.

Herbal therapy is therefore greatly recommended for long term medications of chronic illnesses and for treatment of metabolic disorders, and is often used in combination with clinical homeopathy. Herbal therapy is commonly used to treat asthma, eczema, premenstrual syndrome, rheumatoid arthritis, migraine, and chronic fatigue. A session with a herbalist lasts about one hour and may include a physical exam and a series of questions to establish the patient’s general wellbeing. When prescribing an herb, it is very important to consider the species and variety of the plant, the plant's habitat, how it was stored and processed, and whether or not there are contaminants. The herbalist might recommend one or more herbs, dietary changes, and lifestyle modifications.

Some of the most common herbs used for medicinal purposes are:

St. John's wort: Used for its antidepressant effects.

Valerian: Used for cases of insomnia.

Echinacea preparations: Used to bolster immunity.

However, as many herbal products are unregulated, it is important not to self-prescribe, and to consult a professional herbalist.