Powder (powder) refers to a dry powder solid preparation made by grinding, sieving, and uniformly mixing raw materials (or traditional Chinese medicine decoction pieces, extracts) with suitable excipients, which can be taken orally or externally. It is a simple and primitive dosage form in solid preparations, and also the intermediate basic form of formed dosage forms such as tablets and capsules.

The powder has a small particle size and a large specific surface area, thus it has outstanding characteristics of easy dispersion and fast onset. According to different uses, general powders are fine powders, pediatric and topical powders are fine powders, and ophthalmic powders require higher standards (all pass the No. 9 sieve).