Anzhong San for Stomachache and Acid Regurgitation
Anzhong San comes from the "Taiping Huimin Heji Jufang" (Prescriptions from the Taiping Imperial Pharmacy). It is composed of: Yanhuosuo (Corydalis, peeled) 5 liang (150g), Gaoliangjiang (Lesser Galangal, stir-fried) 5 liang (150g), Ganjiang (Dried Ginger, calcined) 5 liang (150g), Huixiang (Fennel, stir-fried) 5 liang (150g), Rougui (Cinnamon Bark) 5 liang (150g); Muli (Oyster Shell, calcined) 4 liang (120g); and Gancao (Licorice, stir-fried) 10 liang (300g).
Grind the above herbs together into a fine powder. Take 2 qian (6g) each time, mixed with warm wine. If the patient does not drink alcohol, it may be mixed with salt water; women may take it mixed with weak vinegar water. Because Gaoliangjiang, Ganjiang, Huixiang, and Rougui in this formula are all acrid and hot in nature, it must not be used in patients with excess-heat or damp-heat.
This formula warms the interior, dispels cold, and stops pain. It is indicated for stomachache and retching caused by cold stagnating in the spleen and stomach: vomiting of acidic water, fullness and distention in the chest and diaphragm, stabbing pain attacking the abdomen and flanks, nausea and retching, sallow complexion with emaciation, and fatigue of the limbs; or, in women, stabbing pain due to blood-qi disorder, pain in the lower abdomen radiating to the lower back. Today it is often used for reflux esophagitis, chronic gastritis, gastric ulcer, hyperacidity, and cholecystitis presenting the pattern of deficiency-cold of the spleen and stomach.
In this formula, Yanhuosuo, Gaoliangjiang, and Huixiang all relieve pain; Gaoliangjiang and Huixiang also dispel cold. Ganjiang is the sun-dried product of fresh ginger and is more pungent than fresh ginger; it strongly supports yang and dispels cold. Rougui has the same effect as Ganjiang and, in this formula, is used in mutual reinforcement with it to best advantage. Muli neutralizes acid and also has some analgesic effect. Gancao, first, relieves pain; second, harmonizes the other herbs; and third, reduces the irritation that the acrid herbs cause to the gastric mucosa. When all the herbs are combined, they effectively neutralize acid and relieve pain.
In the author's experience, in patients with marked acid regurgitation, this formula may be combined with Wuji San (adding Wuzeigu, Cuttlebone 150g, and Baiji, Bletilla 150g) for an even more pronounced effect. Patients with acid-regurgitation stomachache usually have gastric ulcer and hyperacidity; Cuttlebone neutralizes gastric acid, and Bletilla repairs gastric ulcer well, so adding these two herbs improves the outcome.