Constipation means either feces remaining overlong in the large intestine, so that the interval between defecations is prolonged, or difficult or painful defecation due to dry, large or hard feces.
Etiology and Pathology
Constipation results principally from the large intestine losing its function of transmission. There are four groups of causes.
Heat-Induced Constipation. The first group of causes includes mainly intemperate diet. This may be excessive intake of alcoholic drinks, overindulgence in acrid, spicy or rich foods, or intake of the wrong or poisonous medicinal herbs. Any of these can induce the accumulation of Heat in the stomach and the intestines and injure the body fluids. This in turn leads to dehydration and impedance of the intestinal tract, resulting in Heat-induced constipation. In addition, residual Heat from an illness of exogenous Heat or downward transmission of Dryness-Heat from the lung to the large intestine can also lead to this type of constipation.
Impaired Qi Movement. Excessive melancholy or brooding, insufficient physical activity or overactive Wood Element (liver) suppressing the Earth Element (spleen) can each lead to impedance in the movement of large intestine-Qi. This in turn leads to loss of the functions of descending and downward transmission, so that chyme dwells overlong in the large intestine and turns into Qi-induced constipation. Furthermore, stagnation of Qi can transform into Fire, and accumulated Fire can injure the body fluids. This leads to the drying of feces and difficulty with defecation.
Qi, Yin or Body Fluid Deficiency. A variety of conditions can lead to deficiency of Qi, Yin or body fluids. They include convalescence from a severe illness, having given birth and a weak constitution in the elderly. Excessive use of herbs that induce diaphoresis or catharsis or that dry Dampness can injure Yin-fluids. Excessive physical activity, excessive sweating or overindulgence in sexual activity can injure Qi, blood and Yin-essence. Diabetes can lead to depletion of Yin-fluids. In all these conditions, there is loss of the motive force for the large intestine and the intestinal tract becomes dehydrated. Deficiency-induced constipation ensues.
Deficiency of Yang-Qi. Routine overeating of cold and raw foods or excessive use of bitter and cold herbs can injure Yang-Qi. In senescence or weak constitution genuine Yang is deficient. If Yang-Qi of the spleen and the kidney is deficient, it can no longer warm the body fluids or to moisten the intestinal tract. As a result Yin-Cold gels in the interior, causing blockage in the intestines and impedance of the movement of chyme. This is Cold-induced constipation.
Although constipation is primarily due to the large intestine losing its transmission function, it is intimately related to the functions of other visceral organs, especially the lung, the spleen and the kidney. The lung and the large intestine are related as an interior – exterior dyad. Heat or Dryness in the lung easily extends or transmits to the large intestine. The spleen governs transformation and transportation. Disturbance of these functions leads to stagnation of chyme. The kidney governs the fluids and controls urination and defecation. Deficiency of kidney-essence leads to dehydration of the intestinal tract. Insufficiency of kidney-Yang and decline of the Fire of the vital gate conduce to the gelling of Yin-Cold and loss of intestinal transmission. All these can lead to constipation.
Clinical Manifestation
Constipation is often manifested as a decreased frequency of defecation, that is, longer intervals between successive defecation. In most cases, the frequency is once every 3-5 days, or every 5-7 days. Occasionally, defecation may not come even after half a month; but this is uncommon.
Some patients may defecate at a normal frequency but their feces are very dry and the defecation is difficult or painful. Sometimes, the feces may not even be dry or hard, but because of deficiency of Qi and blood the patient does not have strength to expel the feces or to evacuate completely.
Because constipation causes turbid Qi to fail to descend, abdominal distention may result. There may be abdominal pain, dizziness, distending headache, epigastric discomfort, eructation, anorexia, restless sleep or agitation and irascibility. When constipation is protracted, there may be palpable sausage-like masses in the left lower abdomen. These are masses of accumulated feces; they disappear or decrease following defecation.
In general, even when defecation occurs every 2 or 3 days and the feces are dry, if there is no difficulty or pain and there is no other symptom, the physician should not diagnose constipation.
Key Points of Analysis
Tongue and Its Coating. A red tongue that has little moisture and no or little coating indicates constipation mostly due to insufficiency of blood and fluids. A pale tongue that has little coating indicates constipation mostly due to deficiency of Qi and blood. A white and smooth tongue coating that is not greasy indicates constipation mostly due to internal gelling of Yin-Cold. A thick yellow tongue coating that is dirty and greasy indicates constipation mostly due to Heat accumulation in the stomach and the intestines.
Feces and Defecation. Hard and dry feces and a burning sensation in the anus during defecation indicate gelling of Dryness-Heat in the interior. Hard and dry feces that are difficult to evacuate indicate gelling of Yin-Cold. Feces that are not especially hard or dry but are difficult to evacuate or not evacuated smoothly indicate Qi deficiency.
Palpation of Abdomen. If there is guarding of the abdomen along with constipation, the condition is one of disease evil strength. If there is no guarding but preference for abdominal pressure along with constipation, the condition is one deficiency.
Herbal Treatment
Constipation due to Strength
Heat-Constipation
Main Symptoms. Constipation with dry feces; scant dark urine; and a flushed face and restlessness. Or, fever, dry mouth with halitosis; and abdominal distention or pain. The tongue is red with yellow and dry coating. The pulse is slippery and rapid.
Therapeutic Principle. Cool Heat and moisten the intestines.
Treatment. Pi Yue Maren Wan (Spleen-Restraining Cannabis Pill). If the pills are not available, use the decoction. The composition is as follows: huomaren (Cannabis sativa) 10 g, kuxingren (Prunus armeniaca) 10 g, baishaoyao (Paeonia) 10 g, zhishi (Citrus aurantium) 10 g, houpo (Magnolia) 10 g, raw dahuang (Rheum palmatum) 10 g, and baimi (mel) 10 ml.
If the feces are especially dry and hard, add mangxiao (mirabilite) to soften, purge Heat and promote evacuation.
If the mouth and tongue are dry, indicating damage to body fluids, add shengdi-huang (Rehmannia), xuanshen (Scrophularia), shihu (Dendrobium chrysanthum) and herbs with similar actions to nourish Yin and generate fluids.
If there are hemorrhoids that sometimes bleed, add huaihua (Sophora japonica) and diyu (Sanguisorba) to clear the intestines and stop bleeding.
If depression and rage have injured the liver, with red eyes, irascibility and a taut and rapid pulse, add mudanpi (Paeonia suffruticosa) and zhizi (Gardenia) to soothe the liver and cool Heat.
If Heat-constipation is due to Phlegm-Heat blocking the lung meridian, add huangqin (Scutellaria), gualouren (Trichosanthes) and herbs with similar actions to unblock the lung, moisten the intestines and purge Heat.
Qi-Constipation
Main Symptoms. Difficulty with defecation; frequent eructation; and subcostal and abdominal distention and pain. The tongue coating is thin and greasy, and the pulse taut.
Therapeutic Principle. Smooth Qi movement and remove blockage.
Treatment. Liu Mo Tang (Decoction of Xix Ground Substances). It has the following composition: binglang (Areca) 10 g, wuyao (Lindera) 10 g, muxiang (Aucklan-dia) 10 g, zhishi (Citrus aurantium) 10 g, chenxiang (Aquilaria) 3 g, raw dahuang (Rheum palmatum) 10 g, and yuliren (Prunus japonica) 10 g.
If Qi has been stagnant for a long time and transforms into Fire, with such symptoms as a bitter taste, dry throat, a yellow coating and a rapid pulse, add zhizi (Gardenia), longdancao (Gentiana) and herbs with similar actions to cool Heat and purge Fire.
For pent-up passions, especially melancholy, add chaihu (Bupleurum), baishaoyao (Paeonia), hehuanpi (Albizia julibrissin) and herbs of similar actions to unblock the liver and release the passions.
If the obstruction of Qi movement is due to infestation by parasites, increase the amount of binglang and add vermicides such as leiwan (Polyporus mylittae), feizi (Torreya grandis) and shijunzi (Quisqualis indica).
If Qi-constipation is due to traumatic injury or post-surgical adhesions, it is necessary to mobilize blood and relieve stasis in addition to regulating Qi. Add such herbs as taoren (Prunus persica), honghua (Carthamus), chishoyao (Paeonia) and herbs with similar actions.
If it is due to Phlegm-Rheum obstructing Qi, add zaojia (Gleditsia sinensis), gansui (Euphorbia kansui) and herbs with similar actions to dissipate Phlegm and Rheum and induce catharsis.
Constipation due to Deficiency
Constipation due to Qi Deficiency
Main Symptoms. The feces may be normal and there is desire to defecate, but despite much straining evacuation does not take place. On the other hand, straining induces sweating, shortness of breath and tiredness. There may also be facial pallor, lassitude and reluctance to speak. The tongue is pale and tender, with a white coating. The pulse is feeble.
Therapeutic Principle. Augment Qi and strengthen the spleen.
Treatment. Huangqi Tang (Astragalus Decoction). Its composition is as follows: roasted huangqi (Astragalus) 15 g, dangshen (Codonopsis) 15 g, chenpi (Citrus tangerina) 6g, huomaren (Cannabis sativa) 10 g, danggui (Angelica) 10 g, and baimi (mel) 10 ml.
If deficient Qi sinks and leads to rectal prolapse, add shengma (Cimicifuga), chaihu (Bupleurum), jiegeng (Platycodon) and renshen (Panax) to assist huangqi in augmenting Qi and raising the sunken.
If there is lung insufficiency, with chronic cough and shortness of breath, add Sheng Mai San, ziwan (Aster tartaricus) and baiqian (Cynanchum).
If there is accompanying blood insufficiency, add dried shengdihuang (Rehman-nia) and heshouwu (Polygonum).
For dry feces that are difficult to evacuate, add kuxingren (Prunus armeniaca) and roucongrong (Cistanche).
Constipation due to Blood Insufficiency
Main Symptoms. Dry feces; pallid and lusterless complexion; palpitations of the heart; forgetfulness; dizziness; and blurred vision. The lips and tongue are pale. The pulse is threadlike.
Therapeutic Principle. Nourish blood and moisten Dryness.
Treatment. Run Chang Wan (Intestine-Moistening Pill). It has the following composition: danggui (Angelica) 10 g, dried shengdihuang (Rehmannia) 12 g, huomaren (Cannabis sativa) 10 g, taoren (Prunus persica) 10 g, zhiqiao (Poncirus trifoliata) 10 g, raw heshouwu (Polygonum) 10 g, and baiziren (Biota) 10 g.
If there is Heat arising out of blood insufficiency, with dry mouth, restlessness, a denuded tongue and a rapid threadlike pulse, add yuzhu (Polygonatum), zhimu (Anemarrhena) and herbs with similar actions to generate fluids and cool Heat.
If body fluids have recovered but the feces are still dry, use Wu Ren Wan (Five-Seeds Pill) to moisten and smooth the intestinal tract.
Constipation due to Yin Deficiency
Main Symptoms. Dry feces and emaciation. Or, malar flushing, dizziness, tinnitus, palpitation of the heart, weakness and aching in the waist and knees, and feces like that of goats. The tongue is red, with little coating. The pulse is threadlike and rapid.
Therapeutic Principle. Nourish Yin and strengthen the kidney.
Treatment. Liu Wei Dihuang Tang (Six-Ingredient Rehmannia Decoction) with augmentation. The augmented formula has the following composition: dried shengdihuang (Rehmannia) 12 g, baishaoyao (Paeonia) 10 g, shanzhuyu (Cornus) 10 g, shanyao (Dioscorea) 10 g, mudanpi (Paeonia suffruticosa) 10 g, huomaren (Cannabis sativa) 10 g, xuanshen (Scrophularia) 10 g, yuzhu (Polygonatum) 10 g, maimendong (Ophiopogon) 10 g, and baimi (mel) 10 ml.
Constipation due to Yang Deficiency
Main Symptoms. Normal feces, but much difficulty with evacuation; increased clear urine; pallid complexion; cold hands and feet, with cold-aversion and preference for warmth; and cold pain in the abdomen, or cold heaviness in the waist and spine. The tongue is pale and coating white. The pulse is deep and slow.
Therapeutic Principle. Warm and moisten to ease defecation.
Treatment. Ji Chuan Jian (Blood-Replenishing Decoction). It has the following composition: danggui (Angelica) 10 g, niuxi (Achyranthes) 10 g, roucongrong (Cistanche) 15 g, zhiqiao (Poncirus trifoliata) 10 g, shengma (Cimicifuga) 3 g, processed fuzi slices (Aconitum) 6 g, rougui (Cinnamomum) 3g, and fried gancao (Glycyrrhiza) 6 g.
If there is Qi deficiency as well, add dangshen (Codonopsis) and huangqi (Astragalus).
If there is much nocturia, add jinyingzi (Rosa laevigata), wuyao (Lindera) and shanyao (Dioscorea).
For prominent abdominal pain, add muxiang (Aucklandia) and yanhusuo (Corydalis).
In the elderly with constipation due to Yang deficiency, it is acceptable to use Ban Liu Wan (Pinellia-Sulfur Pill). In this herbal formula, liuhuang (sulfur) is of very hot nature and can replenish genuine Fire of the vital gate. Doing so mobilizes Yang-Qi, so that defecation is facilitated. It is assisted by banxia (Pinellia) for its ability to lower the turbid. With only two ingredients, this herbal formula has a simple composition and very focused action.
Acupuncture Treatment
For treatment of constipation with acupuncture, select Dachangshu (BL-25), Tianshu (ST-25), Zhigou (SJ-6) and other acupoints as needed. For constipation due to disease evil strength apply the reducing method. For deficiency-constipation apply the reinforcing method. For Cold-constipation moxibustion may be applied. For Heat-constipation add the acupoints Hegu (LI-4) and Quchi (LI-11). For Qi-constipation add Zhongwan (CV-12) and Xingjian (LR-2). For constipation due to Qi or blood deficiency add Pishu (BL-20) and Weishu (BL-21). For constipation due to deficiency of Yang-Qi, apply moxibustion at Shenque (CV-8) and Qihai (CV-6).
Case Study
The patient was a 28-year old female. For 5 years she had frequent difficulty with defecation, being able to evacuate only once in 10 days or so. She had abdominal distention and discomfort, poor appetite, dizziness and a lusterless complexion. Her tongue coating was thin and white. Her pulse was threadlike.
Diagnosis. Constipation caused by insufficiency of blood and dry intestines.
Therapeutic Principle. Nourish blood and moisten the intestines.
Treatment and Course. She was prescribed with the following herbs: danggui (Angelica) 10 g, baishaoyao (Paeonia) 10 g, xuanshen (Scrophularia) 10 g, huo-maren (Cannabis sativa) 10 g, baiziren (Biota) 10 g, gualou seed (Trichosanthes) 10 g, heshouwu (Polygonum) 10 g, heizhima (Sesamum indicum) 10 g, and binglang (Areca) 12 g.
After five doses, she was able to defecate every day. Abdominal distension decreased and appetite improved. However, she had a burning sensation in both eyes. Dried shengdihuang (Rehmannia) 12 g was added to the prescription. After several doses, all symptoms disappeared.
