Pohuo San from the "Yangshi Jiacang Fang" for Heatstroke

The "Yangshi Jiacang Fang" (Yang's Family Concealed Prescriptions) records a formula named "Pohuo San." Its composition is: Qing Pi (Green Tangerine Peel, pith removed), Chishao (Red Peony), Huanglian (Coptis, rootlets removed), and Diyu (Sanguisorba Root) in equal parts. Grind the above together into a fine powder. Take 1 qian each time, mixed with fermented grain water; for heat diarrhea, take it mixed with cold water, at any time.

This formula drains fire and cools blood. It treats irritability and thirst caused by heatstroke, bitter mouth and dry tongue, headache and nausea, loss of appetite, bloody dysentery, and heat-induced flooding in women. If the patient has blood-heat reckless movement due to accumulated heat, add an equal amount of Gancao (Licorice).

Heatstroke is a common summer ailment, now also called heat stroke. Severe heatstroke can be life-threatening, so in summer one should avoid prolonged exposure to high temperatures. If headache, nausea, or diarrhea occurs, seek medical care promptly, so as to avoid progression to severe heat stroke that is hard to rescue.

Pohuo San was a common ancient formula for heatstroke. The Huanglian in this formula is the main herb for acute gastroenteritis; modern pharmaceutical companies extract its active ingredient berberine hydrochloride to make berberine tablets (also called berberine hydrochloride tablets), which can also treat acute gastroenteritis.

The Chishao in this formula cools and invigorates blood; Diyu cools blood, stops bleeding, and detoxifies and astringes sores. The two assist Huanglian in nourishing yin, cooling blood, and draining heat and fire. Qing Pi is not easy to buy and may be replaced by Zhishi (Immature Bitter Orange); Qing Pi soothes the liver, breaks qi, and resolves stagnation and accumulation. Heatstroke is often accompanied by acute digestive-tract reactions, and Qing Pi relieves those symptoms.

This formula may be decocted into a fairly thin broth and drunk as tea by heatstroke patients, for even better effect.