Capsule definition: Capsules are divided into hard capsules, soft capsules and enteric-coated capsules.

　　Hard capsule definition：

　　Hard capsules refer to a certain amount of medicinal material extracts plus medicated powder or auxiliary materials into uniform powder or granules, and filled into hollow capsules, or the medicinal powder is directly divided into hollow capsules. The main raw material is gelatin, which should meet the requirements of the pharmacopoeia and has a certain viscosity and jelly power. Gelatin is divided into type A gelatin, type B gelatin, skin gelatin and bone gelatin. Appropriate auxiliary materials are added to ensure the quality of the capsule shell and meet different requirements. The auxiliary materials mainly include:

　　1. Plasticizers such as glycerin can increase the toughness and elasticity of the capsule. Sodium carboxymethyl cellulose can increase the viscosity and plasticity of gelatin liquid;

　　2. Thickeners such as agar can increase the jelly strength of the glue;

　　3. Sunscreen agents such as titanium dioxide can prevent light from catalyzing the oxidation of drugs, the dosage is 2% to 3%;

　　4. Coloring agents such as lemon yellow, carmine, etc. can increase the appearance and facilitate identification;

　　5. Preservatives, such as parabens, can prevent the glue from being mildewed during the preparation and storage process;

　　6. Aromatic flavoring agents such as ethyl vanillin, etc., which can adjust the taste of the capsule, the dosage is 0.1%;

　　7. Brightening agent such as sodium dodecyl sulfonate, can increase the gloss of the capsule shell.

　　Definition of soft capsule:

　　Soft capsule refers to a certain amount of medicinal material extracts and suitable auxiliary materials are sealed in spherical, oval or other shapes of soft capsule materials, prepared by pressing. The soft capsule material is made of gelatin, glycerin or/and other suitable medicinal materials.

　　Composed of rubber (gelatin, gum arabic), plasticizer (glycerin, sorbitol), water, preservative (paraben), sunscreen (titanium dioxide), coloring agent (water-soluble dye for food specifications), aromatic Flavoring agent (ethyl vanillin or essential oil) and other auxiliary materials. Sunscreens, preservatives, coloring agents and other auxiliary materials are the same as hard capsules.

　　Enteric-coated capsules definition：

　　Enteric-coated capsules refer to hard or soft capsules processed by medicinal polymer materials or processed by other suitable methods. Its shell is insoluble in gastric juice, but can disintegrate in intestinal juice to release active ingredients. Commonly used empty gelatin capsules are made by coating enteric polymer materials (such as acrylic resin, cellulose acetate phthalate, etc.), then filling them with drugs, and sealing them with enteric glue.