When faced with the dilemma of treating cold with heat or heat with cold, and when the treatment is ineffective or not appropriate, meaning the illness does not present as purely cold or purely hot, the prescribed herbs cannot solely be cold or hot. Therefore, we must combine cold and hot herbs, which is known as the mutual use of cold and heat.The mutual use of cold and heat is the most widely applicable and variable method in herbal formulations. It can be said that without understanding the mutual use of cold and heat, one cannot be a good doctor.To discuss the method of mutual use of cold and heat, we must first understand the syndrome of mixed cold and heat. This syndrome, where cold and heat are intermingled, can be illustrated with several examples I frequently encounter in clinical practice:1. Cold in the abdomen and heat in the intestines: The patient experiences coldness in the abdomen, with symptoms of fullness, poor appetite, painful lumps upon palpation, refusal to touch, dry mouth, constipation, a dry red tongue, and a dry yellow coating. The pulse shows strength at the cun position and weakness at the chi position. Taking cold herbs exacerbates abdominal pain, while hot herbs lead to mouth sores and abdominal pain. The treatment should include warming herbs such as Gan Jiang (Dried Ginger), Rou Gui (Cinnamon), Fu Zi (Aconite), Ma Ti Xiang (Atractylodes), Sha Ren (Cardamom), and Chang Pu (Acorus) to dispel cold, while also using Huang Qin (Scutellaria), Long Dan Cao (Gentiana), and Da Huang (Rhubarb) to purge the heat in the intestines and stomach. Since these herbs are all drying, we should also add Bai Shao (White Peony), Sheng Di (Rehmannia), Xuan Shen (Scrophularia), and Hua Fen (Pollen) to moisten the intestines and stomach. Additionally, due to the prolonged illness where cold and heat evils contend with the righteous qi, qi tonics such as Dang Shen (Codonopsis) and Huang Qi (Astragalus) must also be included in the formula. Other herbs that promote circulation and resolve blood stasis can be added as needed, making the treatment of this condition manageable.2. Bladder heat and kidney yang deficiency: The patient experiences burning urination, frequent and urgent urination, lower abdominal pain radiating to the waist, and a heavy sensation in the lower abdomen. The pulse is weak at the chi position and strong at the cun position, with a tender red tongue or a red tip, and a pale tender tongue with a thin yellow coating. The treatment should include Xiao Hui Xiang (Fennel), Sha Ren (Cardamom), Du Zhong (Eucommia), Huo Xiang (Agastache), Gan Song (Dried Pine), and Wu Yao (Lindera) to warm and promote kidney qi, along with Che Qian Zi (Plantago), Hua Shi (Talc), Huang Bai (Phellodendron), Wei Zi (Mulberry), Zhi Mu (Anemarrhena), and Shi Wei (Pyrrosia) to clear the heat from the bladder and promote the resolution of the three jiao (upper, middle, and lower burner) heat stagnation. If the dispersing power is insufficient, we can add Hou Po (Magnolia Bark) and Ji Zi (Jujube) to disperse fullness. Since the evil heat has long obstructed and injured the yin, Bai He (Lily), Shi Hu (Dendrobium), and Bai Shao (White Peony) can be used to nourish yin, while Chai Hu (Bupleurum) and Yu Jin (Curcuma) can help clear and disperse stagnation. Adding Tai Zi Shen (Pseudostellaria) and Gan Cao (Licorice) will tonify qi to overcome the evil. Thus, it is clear that this condition requires the mutual use of cold and heat for the formula to be suitable for the symptoms.3. Lung and stomach heat with liver and kidney yang deficiency: The patient presents with heat on the surface, moist skin, lower abdominal pain radiating to the waist, and severe back pain that prevents bending or turning. Due to dryness and heat in the lung and stomach, there is a dry cough with little sticky phlegm, dry mouth, and constipation. The tongue is dry and red or crimson, and the pulse is floating and weak. The patient may also experience sore throat, sweating, or black slippery stools (indicating gastric bleeding). The treatment should follow the method of Wu Mei Wan (Mume Pill) from the “Shang Han Lun” (Treatise on Cold Damage), which combines the mutual use of cold and heat, with sour, bitter, sweet, and spicy flavors. We can consider using Chuan Wu (Chuan Aconite) and Cao Wu (Aconite) to warm the kidney and dispel cold, along with Gan Jiang (Dried Ginger), Wu Zhu Yu (Evodia), Chang Pu (Acorus), Xi Xin (Asarum), and Ma Ti Xiang (Atractylodes) to warm and disperse cold from the surface, allowing the body’s qi to circulate without obstruction. Additionally, a large dose of Huang Bai (Phellodendron) or Da Huang (Rhubarb) can be used to purge heat, complemented by Bai Shao (White Peony), Wu Mei (Mume), Xuan Shen (Scrophularia), and Hua Fen (Pollen) to harmonize and moisten dryness. If there is sweating, add Mu Guo (Papaya); for sore throat, add Jie Geng (Platycodon); for black stools, add Zi Di Yu (Sanguisorba), San Qi (Notoginseng), and Xian He Cao (Agrimonia). Thus, treating this condition is not difficult.4. Heart stasis heat and spleen-stomach cold: The patient experiences palpitations, cyanosis of the lips, fullness and pain in the stomach and hypochondrium, and constipation. The tongue is dry and red with many stasis spots, and the pulse is floating and slippery at the cun and chi positions, with weakness at the chi. This condition may sometimes be accompanied by phlegm and wheezing or numbness and pain in the limbs. The treatment should include Gui Zhi (Cinnamon Twig), Gan Jiang (Dried Ginger), Ma Ti Xiang (Atractylodes), and Wei Ling Xian (Clematis) to warm the middle and disperse obstruction, while also promoting heart yang. Da Huang (Rhubarb) and Da Huang (Rhubarb) can be used to purge heat and resolve stasis, while Bai Shao (White Peony), Sheng Di (Rehmannia) can moisten dryness, and Dang Shen (Codonopsis) and Huang Qi (Astragalus) can tonify qi. Since there is stasis, herbs like Dang Gui (Angelica), Dan Shen (Salvia), Ru Xiang (Frankincense), Mo Yao (Myrrh), Wu Gong (Centipede), Di Bie Chong (Earthworm), and Tao Ren (Peach Kernel) must be included. If the surface is not dispersing, we can add Fang Feng (Saposhnikovia), Qin Jiao (Gentiana), Fang Ji (Stephania), and Du Huo (Angelica) to assist. For wheezing, add Ma Huang (Ephedra), Xing Ren (Apricot Kernel), Sheng Shi Gao (Gypsum), Bai Tou Weng (Pulsatilla), and Bei Mu (Fritillaria) to clear lung heat and transform phlegm (Bai Tou Weng is particularly effective for lung heat phlegm cough). Use Gan Cao (Licorice) to harmonize the properties of the herbs. If wheezing is severe, add Hou Po (Magnolia Bark) and Ting Li Zi (Descurainia); for numbness in the limbs, add Wu Shao She (Bungarus) and Si Guo Luo (Luffa). To prevent excessive purging, it is advisable to add an appropriate amount of Xue Jie (Dragon’s Blood) to moderate the purging effect of Bai Shao (White Peony) and Da Huang (Rhubarb), while also enhancing the formula’s ability to resolve stasis and stasis.5. Wind-cold obstructing the surface, lung and stomach heat accumulation, and kidney yang deficiency: The patient frequently catches colds and suffers for years without recovery, experiencing chills and fever, coughing and sneezing, with a red tongue and yellow coating. The pulse is floating and slippery at the cun position, with weakness at the chi position, and the lower back and limbs feel cold. We can use Hu Zhang (Polygonum) and Da Huang (Rhubarb) to purge the heat accumulation in the lung and stomach, while Fu Zi (Aconite) warms and strengthens kidney yang. Additionally, we can add herbs that disperse the surface and release cold, such as Jing Jie (Schizonepeta) and Fang Feng (Saposhnikovia) to disperse the surface, and Tou Gu Cao (Dichroa) and Qing Feng Teng (Clematis) to release the channels. Due to lower back soreness and weakness, Guo Guo (Euphorbia) and Gou Ji (Cibotium) can tonify the kidney and strengthen the bones. Alcohol is a strong agent for warming and dispersing, and using the above herbs combined in a medicinal wine can combat stubborn conditions that have persisted for years. However, it is crucial to note that the Aconite slices used for the wine must be stir-fried with sand or salt until yellow, and the resulting wine should be consumed in small doses. Following this method, recovery from the illness is not difficult.In summary, the syndrome of mixed cold and heat reflects a wide variety of symptoms. Regardless of how complex the symptoms may be, as long as the patient presents with symptoms that differ from pure cold or pure heat, and both types of symptoms are present, or if the condition worsens after taking either a hot or cold prescription, it is likely a syndrome of mixed cold and heat. In such cases, we should use cold herbs to treat heat and hot herbs to warm cold, combining both to reflect the essence of syndrome differentiation and treatment.Regarding the mutual use of cold and heat in herbs, it is not only applicable to the syndrome of mixed cold and heat but is also widely used in various formulations.For example, regardless of whether the illness is due to external injury, cold transforming into heat, or heat toxins obstructing, causing limb joint redness, heat, and pain, we can refer to ancient formulas such as Tao Zhi Tang (Peach Branch Decoction) and Bai Hu Jia Gui Zhi Tang (White Tiger Decoction with Cinnamon Twig) to use hot herbs to open obstructions and cold herbs to resolve heat toxins. Since heat promotes circulation and cold often causes stagnation, we can add a small amount of Gui Zhi (Cinnamon Twig), Chuan Wu (Chuan Aconite), Cao Wu (Aconite), Gan Jiang (Dried Ginger), and Hua Jiao (Sichuan Pepper) to disperse obstructions. Large doses of cold herbs such as Da Huang (Rhubarb), Huang Bai (Phellodendron), Huang Qin (Scutellaria), and Sheng Shi Gao (Gypsum) can be used to resolve heat toxins. If cold herbs are not assisted by hot herbs, the treatment may lack the ability to promote circulation, making it difficult to reach the limbs and easily damaging the spleen yang, leading to cold accumulation. Only by incorporating a small amount of hot herbs into a large dose of cold herbs can we ensure that hot herbs do not assist heat toxins while allowing the cold herbs to exert their strengths in promoting circulation and resolving obstructions, which is the brilliance of the formulation.Additionally, in cases of spleen and stomach deficiency cold, where prolonged illness has led to yin deficiency and floating heat, the clinical presentation includes fullness and discomfort in the abdomen, persistent pain, preference for warmth and pressure, poor appetite, possible vomiting, or loose stools, fatigue, and weakness. The pulse is thin and wiry, the tongue is tender red with little coating, and there may be heat in the eyes and mouth sores. The treatment should focus on Xiang Sha Liu Jun Tang (Fragrant Sand Six Gentlemen Decoction) to address the deficiency cold, with a small addition of Bai Shao (White Peony), Shi Hu (Dendrobium), Mai Dong (Ophiopogon), and Sha Shen (Glehnia) to moisten and nourish yin, while also using Long Dan Cao (Gentiana) and Huang Qin (Scutellaria) to control the cold that has long been obstructed and accumulated, leading to deficiency heat. This is another example of the mutual use of cold and heat.Furthermore, in cases of spleen and stomach heat accumulation, the patient presents with slippery and rapid pulses, dry and hard stools, abdominal distension and pain, dry mouth, and irritability, with a dry red tongue and yellow dry coating. The treatment should include Da Huang (Rhubarb), Shi Gao (Gypsum), Bai Shao (White Peony), Huang Qin (Scutellaria), Wei Zi (Mulberry), and Long Dan Cao (Gentiana) to clear and purge heat toxins, but a small addition of Mu Xiang (Costus) and Sha Ren (Cardamom) should be included to disperse obstructions. This way, heat toxins can be purged without excessive cold herbs causing abdominal cold or obstructing the flow of qi and blood. The key to effective treatment lies in ensuring that the evil is expelled while maintaining smooth qi flow. Only by harmonizing cold and hot herbs can we better align with clinical realities.In the formulas passed down from predecessors, the mutual use of cold and heat is evident everywhere. For instance, Zhang Zhongjing’s classic formulas include Ban Xia Xie Xin Tang (Pinellia Decoction to Drain the Heart), Fu Zi Xie Xin Tang (Aconite Decoction to Drain the Heart), Wei Zi, Gan Jiang Shi Tang (Mulberry and Dried Ginger Decoction), Wu Mei Wan (Mume Pill), Huang Lian Tang (Coptis Decoction), and Da Huang Fu Zi Tang (Rhubarb and Aconite Decoction), among many others, all of which combine cold and hot herbs according to the balance of cold and heat in the illness, whether leaning more towards cold or heat, or equal amounts of both, ensuring that the cold and heat in the formula counteract the cold and heat of the disease, making formulation not difficult.By learning from the experiences of predecessors and utilizing the rich and diverse herbal combinations available today, we can create effective formulas. Those who do not understand the true meaning of herbal combinations and are busy searching for miraculous herbs will find it difficult to succeed! Each herb has its own bias, and there are fixed actions that are not suitable for certain diseases. If the formulation loses the mutual use of cold and heat, we will be helpless against the adverse effects of herbs that are not suitable for the disease, thus losing the subjective initiative of the formulation. This will inevitably revert to the primitive stage of direct sensory recognition of herbs.
