the ancient Greek theory of the four body humors (blood, yellow bile, black bile, and phlegm) that determined health and disease. The humors were associated with the four elements (air, fire, earth, and water), which in turn were paired with one of the qualities (hot, cold, dry, and moist). A proper and evenly balanced mixture of the humors characterized health of body and mind; an imperfect balance resulted in disease. Temperament of body or mind also was supposed to be determined, sanguine (blood), choleric (yellow bile), melancholic (black bile), or phlegmatic (phlegm).
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Examples: glitazone, GI cocktail, etc.