Decoction

A medicinal preparation made by boiling the ingredients of a formula in water, and then straining off the dregs. Because it was recognized that decoctions prepared in iron pots could have reduced effects, traditional literature stipulates the use of earthenware pots. Pyrex or enamel may now be used. The decoction is the most common medicinal preparation. Decoctions are quickly absorbed by the body, and so are particularly suitable for acute diseases of recent onset. In contrast to ready-prepared pills and powders, decoctions enable the formula to be tailored to the patient’s individual needs.

Materials can usually be boiled twice. The first time, add enough water to cover the materials. The pot is brought to the boil and the contents are given an occasional stir over the 20–30 minute boiling period. The decoction is then strained off. Any materials that swell on absorbing water will have done so during the first boiling so that for the second boiling only enough water is added to cover the materials and a duration of twenty minutes only is required. The two boilings may be mixed together before the patient takes them, in order to ensure even doses.

The water quantities, boiling times, and size of flame given above represent a general guide only. Ideally they are varied according to the medicinals used to ensure maximum benefit. Exterior-effusing and qì-rectifying medicinals are used for their qì rather than their flavor and are cooked over a fierce fire for a relatively short period to prevent the loss of active constituents. Supplementing medicinals are used for their flavor and are therefore boiled for a longer period (about ten minutes longer) over a low flame to ensure complete extraction of active constituents. Compare beverage; brew¹; drink.