Since sweet and tasteless usually coexist, and since sour and astringent drugs have the same effects, pungent, sweet, sour, bitter and salty tastes are the cardinal flavors and are habitually known as five flavors. Drugs of different flavors and different compositions show different pharmacological and therapeutic actions, while drugs of the same taste usually have similarities in effect and even in composition. The flavors don't necessarily refer to the real tastes of the drugs. Sometimes they are sorted out according to drugs' actions other than tastes. Therefore, the flavors of some drugs described in books on materia medica are often different from their true tastes.
Various flavors have different effects.
Drugs that are pungent in flavor have the effects of dispersing exopathogens from superficies of the body and promoting the circulation of the vital energy and blood. Pungent drugs are usually used for the treatment of superficial and mild illnesses due to affection by exopathogens, stagnation of vital energy, blood stasis, etc. Drugs of sweet flavor are usually effective in treating syndromes of deficiency type, dry cough, constipation due to dry intestine, incoordination between the spleen and the stomach, various pains, etc. Besides, some of the sweet drugs have the effects of detoxication. Sour drugs are often used to treat sweating due to debility, chronic cough, chronic diarrhea, emission, spermatorrhea, enuresis, frequent micturition, chronic leukorrhagia, metrorrhagia or metrostaxis, etc.