The dosage of Chinese medicines is often taken on a daily basis. The internal dosage of Huanglian is usually 2~5g per day, and the appropriate amount for external use is sufficient. Huanglian belongs to the traditional Chinese medicine, the dried rhizome of the plant Huanglian, which can clear heat and dry dampness (removing heat and drying out dampness), and also diarrhea fire and detoxification (removing fire, poison and evil qi from the body). It can be used to treat the symptoms of damp-heat lumpiness (stomach distension and discomfort) and vomiting and acid swallowing (swallowing acid that rushes upward from the stomach to the oropharynx), as well as damp-heat diarrhea (diarrhea caused by sensing damp-heat evils), and high fever and dizziness, as well as heartburn and sleeplessness (the symptom of a disturbed heart with heat and insomnia). The usual daily dosage of Huanglian for internal use is 2~5g, while for external use, an appropriate amount can be taken. Adverse effects of Huanglian include dizziness, tinnitus, nausea and vomiting. Contraindications include not to be used with digitalis cardiac glycosides. It should not be used by people with spleen and stomach deficiency (spleen and stomach weakness and cold) and should not be used by people with yin deficiency and fluid injury. When using medication, it is necessary to be guided by a traditional Chinese medicine practitioner to use the medication, do not use the medication arbitrarily, in order to avoid adverse consequences.