Wang, male, 60 years old. Usually weak in constitution and a heavy smoker, he suffered from a common cold cough for over a month. Previous treatment with erythromycin and Heartleaf Houttuynia Herb for four to five days was ineffective. Upon examination, symptoms included cough, slightly yellow-white phlegm, difficulty in expectoration, slight thirst, chest tightness, a red tongue without coating but with excessive saliva, and a fine, soggy pulse. Initially, it was thought to be the inward penetration of an exterior pathogen transforming into heat, consuming the yin of the lung and stomach. Coastal Glehnia Root Ophiopogon Decoction was prescribed with modifications. However, after taking the medicine, not only did the symptoms not improve, but shortness of breath, slightly sticky and thick white phlegm, anorexia, and loose stools also appeared. After careful consideration, it was concluded to be a cough due to the interaction of water and heat. As stated in the "Treatise on Cold Damage Diseases," "In Shaoyin disease, with diarrhea for six to seven days, cough and vomiting with thirst, restlessness, and insomnia, Polyporus Decoction is indicated." Therefore, a prescription to moisten dryness, clear heat, and promote diuresis was given: Polyporus Decoction:
Donkey-hide Gelatin 30g, Polyporus 12g, Poria 10g, Alisma 6g, Talc 24g
. After taking two doses of the above prescription, the symptoms greatly improved, and the pulse became fine and slow. A follow-up prescription to regulate the spleen and lung was then given, leading to a full recovery.