Heat asthma refers to croup caused by intense heat in the lungs, phlegm and rising qi. See "Lei Zheng Zhi Cai·Asthma Theory and Treatment". It is commonly known as phlegm fire. It often occurs in the hot summer season. Symptoms include asthma, phlegm, irritability, heat, dryness and thirst. The treatment should be to clear the lungs and release heat, smooth the qi and resolve phlegm, use Sangbaipi Decoction, Baihu Decoction with Scutellaria baicalensis, Citrus aurantium, and Trichosanthes kirilowii. "Ji Ming Lu·Asthma": "Heat asthma is commonly known as phlegm fire. It is caused by thirst, yellow tongue coating, and short and red urine. Two liang of radish seeds and one liang of weathered saltpeter, grind them together, make honey pills the size of Euryale ferox seeds, and dissolve each pill in the mouth."