First, the dosage forms are classified according to the route of administration:

1. People who take drugs through the gastrointestinal tract have the first-pass effect of the liver, such as oral administration.

2. There is no first-pass effect in the liver of people who are not administered by gastrointestinal tract, such as injection, respiratory tract administration, skin administration and mucosal administration.

2 dosage forms are divided into liquid dosage forms, gas dosage forms, solid dosage forms and semi-solid dosage forms.

Extended data

After the medicine is made into different dosage forms, it is convenient for patients to use and easy to accept, not only the dosage of the medicine is accurate, but also the stability of the medicine is improved, sometimes the toxic and side effects can be reduced, and it is also convenient for the storage, transportation and carrying of the medicine.

Injection includes sterile or sterilized solution, water injection, oil injection and powder injection. The injection has the advantages of quick action, accurate dosage and reliable action. Injection directly enters the human body, and the safety factor is smaller than that of oral dosage form, so it is not recommended to use it first.

Tablets generally include common compressed tablets, sugar-coated tablets, effervescent tablets, chewable tablets, multilayer tablets, implanted tablets, sustained-release tablets, controlled-release tablets and so on. The tablet has the advantages of accurate dosage, stable quality, convenient administration and low price. For sustained-release tablets and controlled-release tablets, the whole tablet should be swallowed when taking medicine. Once chewed up, it can't play a specific role.

Baidu encyclopedia-dosage form