Deficiency syndromes cautions

A side effect of Xi Xin occurs when it is applied incorrectly. Because it is very hot and pungent, it can easily injure the Yin, blood, body fluid and Qi. It should not be used, or must be used with caution, in patients who suffer from exterior wind-cold syndrome where internal heat also coexists and the Yin, blood and body fluids are deficient. The dosage of Xi Xin should also be controlled carefully in the range of 1-3 g per day for crude herbs. If the powdered herbal extract is used, the dosage should be reduced to 0.1 -0.5 g per day. Overdose may cause numbness in the throat and tongue, a stifling... 

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