Drug substance refers to the drug substance used in the production of various preparations. It is the effective ingredient in the preparations. It is the powder, crystal, extract, etc. prepared by chemical synthesis, plant extraction or biotechnology and used as medicine, but cannot be taken directly by patients.

The perfect definition of API in ICH Q7A: any substance or mixture of substances intended to be used in the manufacture of drugs and become an active ingredient of drugs when used in pharmaceuticals. This substance has pharmacological activity or other direct effects in the diagnosis, treatment, symptom relief, treatment or disease prevention of diseases, or can affect the function or structure of the body.

The active ingredient of the drug. Only when raw materials are processed into pharmaceutical preparations can they become medicine for clinical application.

API can be divided into two categories according to its source: chemical synthetic drugs and natural chemical drugs.

Chemical synthetic drugs can also be divided into inorganic synthetic drugs and organic synthetic drugs. Inorganic synthetic drugs are inorganic compounds (very few are elements), such as aluminum hydroxide and magnesium trisilicate used to treat gastric and duodenal ulcers; Organic synthetic drugs are mainly drugs (such as aspirin, chloramphenicol, caffeine, etc.) made from basic organic chemical raw materials through a series of organic chemical reactions.

Natural chemical drugs can also be divided into biochemical drugs and phytochemical drugs according to their sources. Antibiotics are generally produced by microbial fermentation and belong to the category of biochemistry. In recent years, a variety of semi-synthetic antibiotics are products that combine biosynthesis and chemical synthesis. Among the raw materials, the variety, output and output value of organic synthetic drugs account for the largest proportion and are the main pillar of the chemical pharmaceutical industry. The quality of raw materials determines the quality of preparations, so its quality standards are very strict. Countries around the world have formulated strict national pharmacopoeia standards and quality control methods for raw materials widely used.

Drug substance refers to the drug substance used in the production of various preparations. It is the effective ingredient in the preparations. It is the powder, crystal, extract, etc. prepared by chemical synthesis, plant extraction or biotechnology and used as medicine, but cannot be taken directly by patients.

The perfect definition of API in ICH Q7A: any substance or mixture of substances intended to be used in the manufacture of drugs and become an active ingredient of drugs when used in pharmaceuticals. This substance has pharmacological activity or other direct effects in the diagnosis, treatment, symptom relief, treatment or disease prevention of diseases, or can affect the function or structure of the body.

The active ingredient of the drug. Only when raw materials are processed into pharmaceutical preparations can they become medicine for clinical application.

API can be divided into two categories according to its source: chemical synthetic drugs and natural chemical drugs.

Chemical synthetic drugs can also be divided into inorganic synthetic drugs and organic synthetic drugs. Inorganic synthetic drugs are inorganic compounds (very few are elements), such as aluminum hydroxide and magnesium trisilicate used to treat gastric and duodenal ulcers; Organic synthetic drugs are mainly drugs (such as aspirin, chloramphenicol, caffeine, etc.) made from basic organic chemical raw materials through a series of organic chemical reactions.

Natural chemical drugs can also be divided into biochemical drugs and phytochemical drugs according to their sources. Antibiotics are generally produced by microbial fermentation and belong to the category of biochemistry. In recent years, a variety of semi-synthetic antibiotics are products that combine biosynthesis and chemical synthesis. Among the raw materials, the variety, output and output value of organic synthetic drugs account for the largest proportion and are the main pillar of the chemical pharmaceutical industry. The quality of raw materials determines the quality of preparations, so its quality standards are very strict. Countries around the world have formulated strict national pharmacopoeia standards and quality control methods for raw materials widely used.