Ancient — in all likelihood as old as humanity itself — this discipline has its roots in a long history of folk traditions, empirical practices and symbolic and magical meanings. It has now become the subject of the most cutting-edge scientific interest on the part of researchers, ethnopharmacologists and, increasingly, pharmaceutical companies in search of effective active ingredients with fewer side effects.

The growing interest of the market in herbal medicine is evidenced by the proliferation of trade fairs and industry conferences. Moreover, an ever-increasing number of plants are being studied and subjected to chemical, in vitro and in vivo testing, as well as clinical trials. Specialist journals have multiplied as a result, and the fascinating discipline of ethnomedicine — aimed at providing a scientific explanation for the uses of medicinal herbs across the most diverse cultural traditions — is steadily developing.

From a methodological standpoint, herbal medicine differs from conventional medicine solely in its choice of remedies. The approach, in fact, is allopathic. Two aspects, however, set it apart from medicine as commonly practised by the conventional physician: the conception of the plant as a "phytocomplex" — that is, the totality of active ingredients in a synergistic relationship with one another — and of the patient as a complex and multifaceted entity, whose pathological or pre-pathological manifestations are signals of a loss of psychophysical equilibrium. This equilibrium remains the primary target, beyond the manifestations of any one symptom. Herbal medicine, in other words, does not concern itself with the individual symptom or the individual diseased organ, but with the person as a whole.