Gypsum (shi gao)
What is gypsum? What is it used for?
Although it is not an herb, gypsum is nevertheless a vital component of traditional Chinese medicine. It is actually a mineral composed of calcium, sulfur and small amounts of other elements. The most common type of gypsum is fibrous gypsum, which is translucent and has a silky, satiny appearance. It is found throughout the world, especially in the states of Texas and Louisiana in the U.S., and the Hubei, Anhui, Henan and Shandong provinces of China. It is typically found in old ocean beds and sedimentary rocks such as limestone.
In addition to its healing properties, gypsum is used for jewelry and as an ornamental stone. A fine-grained variety of gypsum, known as alabaster, is also used in the creation of ornaments and statues.
In traditional Chinese medicine, gypsum has sweet, pungent and cold properties, and is associated with the Lung and Stomach meridians. Its main actions are to clear excess heat, particularly heat in the lungs and stomach. In modern times, gypsum is used for a variety of ailments, including high fevers, headaches, toothaches and painful gums. It is sometimes taken internally to quench one’s thirst. Topically, gypsum can be applied to the skin to treat eczema, burns and some skin ulcers. It can be taken alone, but is usually employed with herbs such as indigo, coptis, ephedra and anemarrhea.
How much gypsum should I take?
The usual recommended dose of gypsum is between 15 and 60 grams per day, ground into a powder and used as a decoction. Some practitioners may recommend a slightly lower dose (9-30 grams). If gypsum is being used externally, it should be heated (calcined) and pulverized first.
What forms of gypsum are available?
Whole blocks or strands of gypsum can be found at some herbal shops. Gypsum powder is more readily available, either alone or in combination with other herbs.
What can happen if I take too much gypsum?
Are there any interactions I should be aware of?
What precautions should I take?
As of this writing, there are no known cases of gypsum toxicity or interactions with drugs. However, it should not be taken by patients who have insufficient spleen yang, or who have internal heat due to yin deficiency. As always, make sure to consult with a licensed health care provider before taking gypsum or any other dietary supplement or herbal remedy.
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