By Eric Brand and Nigel Wiseman

The standard dose of a medicinal can be varied according to specific factors: the role of the medicinal in a formula; age and constitution; severity and duration of the condition; and the characteristics of the medicinal itself.

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Role in formula: Generally speaking, nontoxic medicinals can be taken in larger quantities when used alone. The chief, or sovereign, medicinal can also be used in larger quantities.

Age and constitution: Harsh and drastic medicinals used to attack disease and dispel evils can damage right qì, and therefore are given in smaller quantities than normal to older patients with debilitation of qì and blood. Children under the age of five should be given a quarter of the standard adult dose. Children of five years or more should be given half the standard adult dose. Elderly and weak patients should be given supplementing medicinals in larger-than-standard doses, but the treat-ment should begin with small doses that are then gradually increased. Drastic supplementing agents such as lù róng (Cervi Cornu Pantotrichum) are unsuitable for use in large doses.

Severity and duration of the pathological condition: For severe acute conditions, large doses are required. For mild, shallow conditions, harsh medicinals that can damage right qì should be used in moderation.

The characteristics of the medicinal: Medicinals that are light in weight, such as leaves and flowers, tend to be used in light doses. Medicinals that are dense and heavy in weight can be used in slightly larger-than-normal doses. Agents with a strong nature and flavor or powerful action should be used in small doses, while medicinals with a weak nature and flavor or mild action can be used in larger quantities. Toxic and harsh agents should be used within their prescribed safety limits.