Purification therapy (shodhana)

Emesis and purgation are said to be the best-known means of purification for removing doshas from the body, as the sages state in the authoritative texts.

Purifying medicine is described as very sharp, hot, mobile (sara) and of vikasi quality, and by these it cleanses upward (emesis) or downward (purgation); the verse also appears to name subtlety (printed सै़म्य).

By the excellence of its qualities the emetic goes upward carrying the unripe doshas, while the purgative goes to the lower part carrying the ripe doshas.

Asking how two medicines alike in qualities do opposite work, the commentary answers that the purgative acts through its sharp and other qualities, while the emetic acts through its specific potency (prabhava).

The best purifying medicines are described as those whose effect has been seen in practice, that are pleasant to take, need only a small dose, are very potent and attractive, and cause few complications; the commentary says such medicines are fit for kings and people like them.

A physician who knows the kinds of bowel gives a dosha-removing purifier to a patient whose bowel he has come to know well, and a gentle, mild purifier to one whose bowel nature is unknown.