Dingxiang Erchen Tang: Cloves Added to Two-Aged Decoction to Harmonize the Stomach, Descend Counterflow, and Stop Vomiting

"Dingxiang Erchen Tang" comes from Yixue Rumen (Introduction to Medicine). Its composition is: tangerine peel (Chenpi) 2 qian (6 g), Poria and Pinellia (Banxia) each 1.5 qian (4.5 g), licorice and patchouli (Huoxiang) each 5 fen (1.5 g), and clove (Dingxiang) 4 fen (1.2 g). Decoct the herbs together in water, strain, add one or two spoonfuls (5–10 ml) of fresh ginger juice, and take warm, twice daily.

This formula warms the middle and resolves phlegm, harmonizes the stomach and descends counterflow. It is indicated for internal retention of cold phlegm with stomach qi counterflowing upward and incessant vomiting. It is a formula built on Erchen Tang (Two-Aged Decoction) plus clove and patchouli, and its action is somewhat stronger than that of Erchen Tang. Erchen Tang also warms the middle and resolves phlegm, harmonizes the stomach and descends counterflow; the clove and patchouli used here are both herbs that descend counterflow and stop vomiting, so adding them makes the descending, antiemetic force greater.

This formula is indicated for nausea and vomiting caused by acute or chronic gastroenteritis, or by food poisoning; it may also be used to relieve nausea and vomiting caused by chemotherapy in cancer patients. The dosage should be light rather than heavy; an excessive dose not only fails to descend counterflow and stop vomiting but will prove counterproductive and worsen the patient's condition. If, besides nausea and vomiting, the patient also has diarrhea, then Coptis (Huanglian) 2–4 fen (0.6–1.2 g) and perilla (Zisu) 3 g should be added to the base formula.