The capsule is just a kind of decoration or vest of medicine. Of course, it is not only used to make them look good, but also mainly to make them easy to take and achieve the best curative effect.
According to historical records, the first capsule used by humans was created in Egypt 1500 years ago. At that time, it was not clear whether the capsule was purely for packaging drugs. However, from 1730, pharmacists in Vienna began to use starch to make what was then called vegetable capsules. At this point, it is clear that capsules are used to package drugs. This capsule production technology was patented in Paris in 1834.
Drugs taken by patients when they are ill must be digested and absorbed into the blood through the gastrointestinal tract, and then decomposed by the liver. However, a considerable number of powders, granules, liquids, tablets or other substances are bitter and irritating, volatile or decomposed by saliva in the mouth. Some drugs may also be inhaled into the airway, causing side effects. Therefore, putting the drug into the capsule can protect the mouth and digestive tract, facilitate swallowing, and make the drug play its best role.
In order to obtain the best drug, it is equally important to prevent it from destroying a person's gastric acid. Because some drugs need to be dissolved in the intestinal tract for absorption, the substances made of capsule like special membrane materials (such as gelatin, cellulose, polysaccharide, etc.) need to be encapsulated with various types of drugs, such as powder and liquid, according to the dosage.
In addition, the drug has a half-life, which refers to the time required to halve the maximum concentration of the drug in the blood. The half-life of a drug reflects the rate of excretion (excretion, biotransformation, storage, etc.) of the drug in the body, and reflects the relationship between the time of the drug in the body and the blood drug concentration. Therefore, it is the main basis for determining the dosage and frequency of administration. Drugs with a long half-life are slowly eliminated in the body with a longer use interval, while drugs with a short half-life are rapidly eliminated in the body with a shorter use interval.
