Enteric coated drug delivery capsule. Coloured scanning electron micrograph (SEM) of an open drug delivery capsule (blue), showing the drug particles (orange) inside. The outer layer (blue) has an enteric coating that resists being digested by the stomach. When it reaches the small intestine the coating breaks down and releases the drug particles inside. This allows the drug to be delivered to the correct part of the intestine. Microparticle delivery systems such as this are used to treat conditions such as Crohn's disease.