At present, there are many different drug dosage forms from tablets and punches to injections and aerosols. However, most of these conventional dosage forms, whether oral or injectable, need to be administered several times a day, which is not only inconvenient to use, but also the drug concentration in the blood fluctuates greatly, showing the phenomenon of “peaks and valleys”. When the drug concentration is at its peak, it will exceed the appropriate therapeutic concentration, causing more adverse reactions and even poisoning; on the contrary, when the drug concentration drops to a low point, it is far below the required concentration, making it difficult to play the drug effect. Therefore, new drug dosage forms – slow release formulations and controlled release formulations have come into being. They can control the speed of drug release to reduce or avoid the “peak and valley” fluctuation of blood concentration. Sustained-release drugs: The drug is first made into small particles and divided into several parts. A small number of uncoated is the immediate release part, and the others are wrapped with different thicknesses of “coat” for the slow release part, and then take the above particles and mix them in a certain ratio to make a certain dosage form, and then release the drug sequentially within the required time according to the different thicknesses of uncoated and coated, so as to continuously exert therapeutic effects. Controlled-release drugs: the drug is released to the outside through the controlled-release coating at a regular, quantitative and uniform rate, so that the blood. The drug concentration is constant and there is no “peak and trough” phenomenon, so that the efficacy can be better. Generally, the core of the tablet containing the drug is first made, and then a certain thickness of semi-permeable membrane is wrapped around the core, and then a number of small holes are punched in the membrane by laser technology, after the patient takes it, the drug comes into contact with body fluids and water enters the core from the semi-transparent membrane to dissolve the drug, and when the osmotic pressure inside the tablet is higher than that outside, the drug will flow out slowly from the small holes and work well. For example, the nitroglycerin tablets commonly used to prevent angina pectoris, each time sublingual 1 tablet, can only maintain the effect of about 3o minutes, the time is short, easy to attack in the evening. The controlled-release patch consists of a protective layer, a pay layer, a controlled-release film, a drug store and an aluminum foil, etc. The drug is released continuously at a constant rate through the microporous semi-permeable membrane by means of osmotic pressure and absorbed into the bloodstream through the skin, maintaining a stable therapeutic concentration, so that only one dose is needed each day to maintain the therapeutic effect for about 24 hours, which not only reduces the number of doses, but also improves and prolongs the therapeutic effect, reduces toxic side effects, and prevents It can also prevent nocturnal angina attacks. This is also the case with Bexinom for hypertension. If you have experience, you will find that the next day when you have a bowel movement, you will find that the Bactrim is “prototypically discharged”, and then look closely, there is a very small hole on one side of the Bactrim, and this hole is the hole for the slow release of the drug. The invention of controlled release or extended release agents also solves the problem of convenient use when patients travel, travel or go to the field work, from multiple doses to a single dose. This shows that the slow-release, controlled-release drug tablets or capsules, chewed or broken into pieces is strictly prohibited.