Shenqi Wan: A Classical Formula for Cancer-Related Diarrhea
Shenqi Wan (Four-Miracle Pill) is recorded in Yi Fang Ji Jie (Systematic Explanation of Medical Formulas). It consists of four herbs—Psoraleae Fructus (Bu Gu Zhi), Schisandrae Fructus (Wu Wei Zi), Myristicae Semen (Rou Dou Kou), and Evodiae Fructus (Wu Zhu Yu)—together with Zingiberis Rhizoma (Sheng Jiang) and Jujubae Fructus (Hong Zao Rou). It treats spleen-kidney deficiency-cold leading to pre-dawn diarrhea (wuxiexie), poor appetite, indigestion, abdominal pain with cold limbs, fatigue and lassitude, a pale tongue with thin white coating, and a deep, slow, forceless pulse. Because of its reliable efficacy, modern pharmaceutical companies produce it as a Chinese patent medicine, available in many pharmacies and online drugstores.
The formula for Shenqi Wan published in the 2010 edition of the Pharmacopoeia of the People's Republic of China, Volume I, is: Psoraleae Fructus (Bu Gu Zhi) 400 g, Myristicae Semen (Rou Dou Kou) 200 g, Schisandrae Fructus (Wu Wei Zi) 200 g, Evodiae Fructus (Wu Zhu Yu) 100 g, Jujubae Fructus (Hong Zao) 50 pieces (pitted), Zingiberis Rhizoma (Sheng Jiang) 200 g, together prepared into pills. The finished product is a light brown or brown water pill, with a slightly aromatic odor and a bitter, salty taste mixed with sour and pungent notes. Adults take 9 g each time, 1–2 times daily.
Shenqi Wan is mainly used clinically to treat diarrhea, and its effect on "pre-dawn diarrhea" is particularly remarkable. This formula heavily uses Psoralea (Bu Gu Zhi), which is pungent, bitter, and warm; TCM holds that it can both tonify the fire of the Mingmen (Life Gate) and warm and nourish the spleen earth. The Bencao Gangmu (Compendium of Materia Medica) states that it has the effect of "treating kidney diarrhea." Myristica (Rou Dou Kou) is pungent and warm; TCM holds that it warms the spleen and stomach and astringes the intestines to stop diarrhea. Schisandra (Wu Wei Zi) is sour and warm; TCM holds that it consolidates the kidney and boosts qi, astringes essence and stops diarrhea. Evodia (Wu Zhu Yu) is pungent, bitter, and very hot; TCM holds that it warms the spleen and stomach to disperse yin-cold. Jujube (Da Zao) tonifies the spleen and nourishes the stomach, while fresh ginger warms the stomach and dispels cold. When these six are combined, they have an excellent effect on pre-dawn diarrhea due to kidney-yang deficiency.
Cancer patients are prone to diarrhea, medically termed cancer-related diarrhea. Diarrhea in cancer patients may be caused by the cancer itself—for example, colorectal cancer patients present with diarrhea—or by various treatments: patients undergoing surgery, radiotherapy/chemotherapy, or targeted therapy are also prone to diarrhea. Shenqi Wan has a certain therapeutic effect on cancer-related diarrhea. Whether taken orally or ground into powder and applied externally to the navel (Shenque point), it has some antidiarrheal effect.
Modern pharmacological research has found that Shenqi Wan has good therapeutic effects on both drug-induced diarrhea and diarrhea caused by intestinal flora imbalance. It significantly inhibits the spontaneous movement of isolated rabbit intestinal segments and can counteract intestinal spasm induced by acetylcholine and barium chloride. Therefore Shenqi Wan is also commonly used to treat nonspecific enteritis, ulcerative colitis, and intestinal tuberculosis. Besides treating diarrhea, Shenqi Wan can also treat frequent urination due to kidney-yang deficiency.
Clinically, Shenqi Wan is differentiated by the pattern of pre-dawn diarrhea, loose stools with undigested food, clear and profuse urine, a deep, slow, forceless pulse, lower back soreness, and cold limbs—all signs of kidney-yang deficiency in traditional TCM. It is ineffective for diarrhea due to damp-heat pouring downward; this type is often accompanied by dark, scanty urine and difficult, dribbling urination. Such patients should be treated primarily with Coptis-containing formulas; using Shenqi Wan would instead worsen their symptoms. Therefore, when selecting drugs and formulas, one must carefully differentiate the patient's pattern.