There are two main types of sustained-release technologies for oral dosage, one is membrane sustained-release, and the other is matrix sustained-release membrane sustained-release, which is equivalent to building a house to close the drugs, leaving only a small door for them to come out slowly.

　　The sustained release of the matrix is ​​equivalent to entanglement of the drug with a ball of aquatic plants so that they can only be released slowly. There are many specific technologies. Some insoluble polymer materials will be used for the sustained release of membranes.

　　The framework materials can be insoluble, hydrophilic gels or bioerodible materials. The membrane material can release the drug by adjusting the ingredients to naturally form some micropores, or it can be punched by laser. In addition, the drug pellets can be wrapped with a release retarding material to achieve a sustained release effect, which can be a combination of coatings of different thicknesses, or multiple coatings.

　　Sustained-release capsules use this principle. The pellets inside have different coatings, and the time to dissolve the drug is also different. Then, a combination of several pellets with different drug release speeds will release more smoothly as a whole.

　　Simply put:

　　That is, the drug will not be released in full in the body immediately, it will be gradually released, and the body will continue to absorb as the drug is released, so that the blood drug concentration will not become too high at once, and the drug will continue to enter the body.

　　It reduces the trouble of taking medicine and keeps the blood concentration stable, which can reduce the side effects of the medicine.