These medicines are metabolic stimulants. In general, they promote metabolism, increase circulation, enhance digestion, and increase bio-availability of medicines they are combined with. This class of medicines was said to increase Digestive Fire (Agni) in Ayurveda (Spleen Yang in TCM), and to digest Ama (toxic residue left from undigested food, similar to Damp of TCM).
    
They are not so commonly used alone, but are very often added to traditional formulas.

Used with other Medicines:

1. With Qi tonics to Warm the Yang. This combination is used to warm and strengthen the Spleen, Heart and Kidneys when obstructed by Cold accompanied by deficiency.
2. With Qi moving medicines to warm, dry, and clear Cold and Damp. Commonly used to stimulate digestion, promote urine and promote Menstruation when obstructed by Cold.
3. With Diuretics to help clear Cold, Damp and Water.
4. With Heat-clearing (Cold) medicines to prevent them from cloying, stagnating and causing obstruction. This also increases their efficacy so that smaller doses work more effectively.

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