1Overview
Damp-Heat is a term in Traditional Chinese Medicine (TCM) referring to pathogenic factors, classified among the six excesses: wind, cold, summer heat, dampness, dryness, and fire (heat). It is also a TCM syndrome, known as Shī Rè Zhèng (湿热证), which indicates the accumulation of damp-heat within the body, obstructing the functioning of the organs and meridians, leading to pathological changes associated with damp-heat symptoms throughout the body.
The term damp refers to what is commonly understood as moisture, which can be categorized into external dampness and internal dampness. External dampness is considered an external pathogen, known as Shī Xié (湿邪), often caused by humid climates, exposure to rain, or living in damp environments, leading to the invasion of external moisture into the body. Its pathogenic characteristics include heaviness, stickiness, and a tendency to descend. Internal dampness is a pathological product related to dysfunction of the organs.
Heat is also a type of pathogenic qi, characterized by its inflammatory and ascending nature, referred to as Huǒ Rè Zhī Xié (火热之邪). Heat can also arise from dysfunction of the body’s organs, termed Nèi Rè (内热). When heat from external pathogens invades the body or when internal heat arises from organ dysfunction, it can lead to heat syndromes. Clinical manifestations of heat syndromes include fever, thirst with a preference for cold drinks, flushed face and red eyes, short and dark urine, dry and hard stools, a red tongue with a yellow and dry coating, and a rapid pulse.
Damp-Heat occurs when both heat and dampness simultaneously invade the body or coexist within it. This can happen during the hot and humid summer and autumn seasons, or when dampness lingers and transforms into heat. Common clinical manifestations of damp-heat syndrome include fever, a sensation of heat without relief, heavy and painful head and body, bitter taste in the mouth, chest fullness, yellow and short urine, a red tongue with a yellow and greasy coating, and a slippery and rapid pulse. When damp-heat affects the joints, it is termed Shī Rè Bì Zhèng (湿热痹证); when it invades the organs, it can lead to conditions such as Pí Wèi Shī Rè (脾胃湿热), Gān Dǎn Shī Rè (肝胆湿热), Páng Guāng Shī Rè (膀胱湿热), and Dà Cháng Shī Rè (肠道湿热).
2Etiology
The formation of damp-heat syndrome can be attributed to four main causes:
1. Invasion of External Pathogens
This primarily involves the invasion of damp-heat pathogens. Located in the Northern Hemisphere, China experiences a transition between summer and autumn when heat and humidity peak, leading to the invasion of damp-heat into the body and resulting in illness. In the southeastern coastal regions, humidity is prevalent throughout the year, especially from March to May, known as the “plum rain season,” when the weather becomes warmer and dampness combines with heat, making it easier for damp-heat to develop. Other external pathogens, such as wind-heat, can also combine with internal dampness due to spleen deficiency, leading to damp-heat. As Xue Shengbai stated: “When the sun is internally injured, dampness accumulates, and external pathogens invade, leading to damp-heat due to the interaction of internal and external factors.” Additionally, when external pathogens invade the lungs, causing chest tightness and cough, it can harm the spleen and stomach, leading to internal dampness and subsequent transformation into heat, resulting in damp-heat.
2. Dietary Irregularities
Excessive consumption of rich, greasy foods can generate dampness and heat; overindulgence in alcohol, overeating, and consuming unclean food can harm the spleen and stomach, causing food stagnation, damp obstruction, and qi stagnation. Prolonged food stagnation, damp obstruction, and qi stagnation can transform into heat. The nature of alcohol is “qi-heat with dampness,” and qi stagnation is a significant factor in the accumulation of dampness. Rich and greasy foods are particularly effective in generating dampness and heat, indicating that various dietary irregularities can contribute to the accumulation of damp-heat.
3. Spleen and Stomach Dysfunction
Internal dampness can arise and transform into heat. The spleen is responsible for the transformation and transportation of fluids, and any damage to the spleen and stomach can lead to dysfunction in their ability to process fluids, resulting in internal dampness. Prolonged damp obstruction can transform into heat, leading to damp-heat syndrome.
4. Emotional Factors
The spleen is associated with thought, and excessive thinking can lead to qi stagnation. Zhang Jingyue once said: “Excessive thinking can harm the spleen.” Overthinking and emotional distress can affect the liver’s ability to regulate qi, which is essential for the spleen’s ability to ascend and the stomach’s ability to descend, maintaining the healthy movement of spleen qi. When the liver fails to regulate qi, the spleen’s function is impaired, leading to the generation of dampness, which can transform into heat, resulting in damp-heat and potentially causing liver-gallbladder damp-heat or spleen-stomach damp-heat.
The aforementioned causes can lead to different manifestations of damp-heat syndrome in different individuals, such as invasion by external damp-heat pathogens, excessive consumption of rich foods, or spleen and stomach dysfunction leading to internal dampness and heat transformation, resulting in liver-gallbladder damp-heat syndrome; or when damp-heat external pathogens invade the body, or excessive consumption of rich foods and alcohol leads to internal dampness and heat accumulation in the middle jiao, resulting in spleen-stomach damp-heat syndrome; if damp-heat invades the large intestine, causing obstruction and qi stagnation, it leads to large intestine syndrome; if external damp-heat invades the bladder, or dietary irregularities lead to internal dampness, resulting in bladder damp-heat syndrome with abnormal urination; if damp-heat flows into the joints, causing localized redness, swelling, and pain, it results in damp-heat bi syndrome.
3Clinical Manifestations
The general manifestations of damp-heat include: a heavy sensation in the head and body, fever that is more pronounced in the afternoon, and a sensation of heat that does not diminish with sweating; a yellow and greasy tongue coating, and a rapid pulse. Specific manifestations vary depending on the location of damp-heat: on the skin, it may present as eczema or sores; in the joints and tendons, it may cause localized swelling and pain. However, damp-heat typically refers to deep infiltration into the organs, especially the spleen and stomach, which can present as fullness and discomfort in the epigastrium, nausea, aversion to food, loose stools, short and dark urine, and a slippery and rapid pulse; liver-gallbladder damp-heat may present as distension and pain in the liver area, bitter taste, poor appetite, jaundice, alternating fever and chills, and a wiry and rapid pulse; bladder damp-heat may present as frequent and urgent urination, burning pain during urination, yellow and turbid urine; large intestine damp-heat may present as abdominal pain and diarrhea, even with tenesmus and purulent or bloody stools, burning sensation in the anus, and thirst.
4Differential Diagnosis
1. Damp-Heat Syndrome
Main manifestations include bitter mouth, dry mouth, sticky sensation in the mouth, thirst with a lack of desire to drink, flushed face and red lips, oral ulcers, high fever, body heat that does not diminish, especially in the afternoon, headache, heavy body, aversion to oily foods, lack of appetite, fullness in the upper abdomen, abdominal pain, tenesmus, red tongue with a yellow and greasy coating, slippery and rapid or wiry pulse.
2. Cold-Damp Syndrome
Main manifestations include fullness in the epigastrium, poor appetite, nausea and vomiting, abdominal pain relieved by warmth and pressure, fatigue, loose stools, cold pain in the lower back and limbs, and a sensation of coolness in the lower abdomen, with pain worsening in cold or damp weather, dull pain that is persistent or worsens at night, white tongue coating, and a deep and tight or wiry and slow pulse.
5Pattern Identification and Treatment
The treatment of damp-heat generally involves distinguishing whether dampness or heat is predominant. If dampness is predominant, the treatment focuses on resolving dampness, using formulas such as Liù Yī Sǎn (六一散), Sān Rén Tāng (三仁汤), or Píng Wèi Sǎn (平胃散); if heat is predominant, the treatment focuses on clearing heat, using formulas such as Lián Pǔ Yǐn (连朴饮), Yīn Chén Hāo Tāng (茵陈蒿汤), or even Gè Gēn Qín Lián Tāng (葛根芩连汤). Based on this principle, specific herbs can be selected according to particular symptoms, such as adding Yě Jú Huā (野菊花), Dì Dīng Cǎo (地丁草), Kǔ Shēn (苦参), and Bái Xiǎn Pí (白藓皮) for eczema or sores; adding Guì Zhī (桂枝), Rén Dōng Téng (忍冬藤), and Sāng Zhī (桑枝) for joint swelling and pain; adding Bái Tóu Wēng (白头翁), Dì Yú (地榆), and Chē Qián Zǐ (车前子) for diarrhea or dysentery; adding Lóng Dǎn Cǎo (龙胆草) and Kǔ Shēn (苦参) for scrotal eczema, testicular swelling, and yellow foul discharge; and adding Xiǎo Jì Cǎo (小蓟草), Máo Gēn (茅根), Shí Wěi (石苇), and Biǎn Xù (扁蓄) for hematuria.
1. Spleen-Stomach Damp-Heat Syndrome
Symptoms: fullness and discomfort in the epigastrium, nausea, aversion to food, loose stools, short and dark urine, slippery and rapid pulse. Treatment principle: clear heat and resolve dampness. Main formula: Huò Pò Xià Lín Tāng (藿朴夏苓汤). Ingredients: Huò Xiāng (藿香), Hòu Pò (厚朴), Bàn Xià (半夏), Fú Lìng (茯苓), Xìng Rén (杏仁), Yì Yǐ Rén (薏苡仁), Bái Kòu Rén (白蔻仁), Zhū Lǐng (猪苓), Zé Xiè (泽泻), Dàn Dòu Chǐ (淡豆豉), or use Wáng Shì Lián Pǔ Yǐn (王氏连朴饮). Ingredients: Hòu Pò, Jiāng Zhī Chuān Lián (姜汁川连), Shí Chāng Pú (石菖蒲), Zhì Bàn Xià (制半夏), Xiāng Chǐ (香豉), Jiāo Zhī (焦栀), Lú Gēn (芦根).
2. Liver-Gallbladder Damp-Heat Syndrome
Symptoms: distension and pain in the liver area, bitter taste, poor appetite, jaundice, alternating fever and chills, wiry and rapid pulse. Treatment principle: clear heat and promote dampness resolution. Main formula: Lóng Dǎn Xiè Gān Tāng (龙胆泻肝汤). Ingredients: Lóng Dǎn Cǎo, Chái Hú (柴胡), Zhī Zǐ (栀子), Dà Huáng (大黄), Huáng Qín (黄芩), etc.
3. Large Intestine Damp-Heat Syndrome
Symptoms: abdominal pain and diarrhea, even with tenesmus and purulent or bloody stools, burning sensation in the anus, thirst, short and yellow urine, red tongue with a yellow and greasy coating, slippery and rapid pulse. Treatment principle: clear heat, resolve dampness, and promote qi movement. Main formula: Bái Tóu Wēng Tāng (白头翁汤). Ingredients: Bái Tóu Wēng, Huáng Bǎi (黄柏), Huáng Lián (黄连), Qín Pí (秦皮), Huò Xiāng, etc.
4. Bladder Damp-Heat Syndrome
Symptoms: frequent and urgent urination, burning pain during urination, yellow and turbid urine, fullness and discomfort in the lower abdomen, possibly accompanied by fever and low back pain, hematuria, or presence of sand or stones in urine, dry stools, red tongue with a yellow and greasy coating, rapid pulse. Treatment principle: clear heat and resolve dampness. Main formula: Bā Zhèng Sǎn (八正散). Ingredients: Jīn Qián Cǎo (金钱草), Chē Qián Zǐ, Mù Tōng, Dàn Zhú Yè (淡竹叶), Dà Huáng, Yì Mǔ Cǎo (益母草), Zé Xiè, Fú Lìng, Biǎn Xù, Shí Wěi, etc.
5. Damp-Heat Bi Syndrome
Symptoms: pain and discomfort in the joints and limbs, or redness and swelling in the joints, possibly with chills and fever, pale yellow complexion, dry mouth with a lack of desire to drink, yellow and greasy tongue coating, red tongue, slippery and rapid or slippery pulse. Treatment principle: clear heat and relieve bi. Main formula: Bái Hǔ Jiā Zhú Tāng (白虎加术汤). Ingredients: Cāng Zhú (苍术), Shí Gāo (石膏), Zhī Mǔ (知母), Jīng Mǐ (粳米), etc.
6Prevention
1. Daily Health Maintenance
Damp-heat often relies on dampness for its existence, so it is essential to improve living conditions and dietary habits. Avoid overeating, excessive alcohol consumption, and the intake of greasy foods to maintain good digestive function and prevent internal dampness or external dampness from invading the body. It is crucial to limit sweet foods, sweet beverages, and spicy or stimulating foods, and to reduce alcohol consumption (which is a significant contributor to damp-heat). A light diet that promotes dampness resolution is recommended. Foods that help eliminate dampness include mung beans, winter melon, loofah, adzuki beans, watermelon, green tea, and flower tea.
2. Dietary Therapy
(1) Ingredients: squab, yam, poria, goji berries, longan, lotus seeds, red dates, coix seeds. Method: Slow-cook for 3 hours. Effect: nourishes the heart, strengthens the spleen, tonifies the kidneys, boosts qi, and resolves dampness.
(2) Ingredients: isatis root, pig shank, 1 slice of ginger, half a piece of honey date. Method: Clean the pig shank (the meat from the front lower leg of the pig) and cut it into large pieces. Rinse the isatis root slices, then place all ingredients into a stewing pot and cook on high heat for 3 hours, adding salt to taste before serving.
(3) Ingredients: earth poria, water snake, 2 red dates, 1 slice of ginger. Method: Cut the water snake into sections, wash clean, and blanch briefly. Peel and slice the earth poria. Place all ingredients into a stewing pot and cook on high heat for 3 hours, adding salt to taste before serving.
(4) Ingredients: fresh mulberry leaves, pig shank, half a piece of honey date, 2 slices of ginger. Method: Clean the pig shank and cut it into large pieces. Rinse the fresh mulberry leaves, then place all ingredients into a stewing pot and cook on high heat for 3 hours, adding salt to taste before serving.
(5) Ingredients: 1 carp, fresh bamboo shoots, watermelon rind, broad beans, ginger, and red dates in appropriate amounts. Specialty: resolves dampness and turbidity, strengthens the spleen, and promotes urination. Suitable for those with heaviness, fatigue, and short urination; also beneficial for hypertension with damp-heat and spleen deficiency. Bamboo shoots are low in fat, low in sugar, and high in fiber, promoting intestinal peristalsis, aiding digestion, preventing constipation, and having anti-cancer properties. Method: Peel the bamboo shoots, soak them in water for a day; clean the carp, remove the gills and entrails without removing the scales, and lightly fry until golden; wash the broad beans, watermelon rind, ginger, and red dates (pitted). Place all ingredients into boiling water, bring to a boil, then simmer for 2 hours, seasoning with salt before serving.
(6) Ingredients: medium to large loach, chicken breast, pig spare ribs, corn silk, 1 green onion, several slices of ginger. A pinch of salt and a few drops of sesame oil. The loach is sweet and neutral, tonifying the middle and benefiting the kidneys, while corn silk is sweet and neutral, calming the liver and clearing heat, promoting urination and resolving dampness. Stewing with pig spare ribs and chicken breast is effective for diabetes, urinary tract infections, carbuncles, hypertension, and jaundice. Method: Cut open the loach, clean it, blanch it in boiling water, and drain. Cut the pig spare ribs into pieces and place them in a clay pot, adding the loach. Add ginger, green onion, and enough boiling water; tie the corn silk in a cloth and place it in the pot. Simmer until about 60% cooked, then add shredded chicken breast and continue cooking until tender. Remove the ginger, green onion, and corn silk before serving, seasoning with salt and sesame oil.
(7) Ingredients: yellow soybeans (edamame) and pork ribs. This soup has effects of eliminating damp-heat, resolving dampness, relieving gastrointestinal dryness, detoxifying, and treating athlete’s foot and damp bi. Yellow soybeans are rich in protein, fat, and vitamin B1; moderate consumption is beneficial, while excessive consumption can lead to obesity. Method: Soak the yellow soybeans for 15 minutes, clean the pork ribs, marinate with a little salt for half an hour, then cut and place in a pot, adding yellow soybeans and 4 to 5 bowls of water, simmering for 2 hours until the soybeans are soft and the soup is ready.
(8) Ingredients: white grass root, corn silk, red dates, pig small intestine. This soup can resolve dampness and reduce swelling. Method: Clean the pig small intestine, cut it into pieces, rub with salt and starch, then rinse. Boil in water for 15 minutes, then rinse in clean water. Remove the pits from the red dates, wash them along with the white grass root and corn silk, soak briefly, then place them with the pig small intestine in a clay pot, adding about 8 bowls of clean water. Boil on high heat, then simmer for 2 hours, adding salt and a little oil to taste.
(9) Ingredients: dried mussels (washed), yam, job’s tears, and a piece of mountain fish (wrapped in a filter bag). Method: Use appropriate amount of water, simmer for about 3 hours, and season to taste. Effect: clears lung heat, eliminates phlegm-fire, promotes urination, and resolves dampness. Indications: lung dryness and heat, pale tongue with a white coating, throat itchiness, yellow urine, and constipation.
(10) Ingredients: soybean sprouts, 1 zucchini, sardines (or large-eyed chicken fish), ginger. Method: Use appropriate amount of water, simmer for about 1 hour, and season to taste. Effect: clears heat and resolves dampness, preventing pharyngitis. Indications: body heat, sore throat, and red and hot urine.
(11) Ingredients: old cucumber (seedless), dried tangerine peel, glutinous rice, and 2 fresh duck kidneys (blanched). Method: Use appropriate amount of water, simmer for about 3 hours, and season to taste.
(12) Ingredients: zucchini, raw coix seeds, dried mussels (washed), and dried tangerine peel. This is a soup of zucchini, coix seeds, and dried mussels, effective for clearing summer heat and resolving dampness, strengthening the spleen, and stimulating appetite. Indications: fatigue, and difficulty urinating. Method: Use appropriate amount of clean water, simmer for about 1.5 hours, and season to taste.
(13) Píng Ān Chá (平安茶): Mián Yīn Chén (绵茵陈), Chuān Rén Dōng (川忍冬), Chuān Jiā Pí (川加皮), Xià Kū Cǎo (夏枯草), Huò Xiāng, Gān Cǎo (甘草), Gǔ Yá (谷芽). This tea can gently resolve dampness, clear heat, eliminate stagnation, and promote bowel movements. Method: Boil 3.5 bowls of water until reduced to 1 bowl for consumption, effective for resolving dampness, eliminating stagnation, clearing heat, and calming the liver.