Severity grading helps to choose the correct treatment plan. At present, it is classified according to the international improvement method:

1. Mild (Grade I): acne is the main symptom, with a few papules and pustules, and the total lesions are less than 30;

2. Moderate (Grade II): acne, moderate number of papules and pustules, with 30-50 total lesions;

3. Moderate (Grade III): a large number of papules and pustules, occasionally large inflammatory lesions, widely distributed, with the total number of lesions ranging from 5 1 ~ 100, less than 3 nodules;

4. Severe (Grade IV): nodular, cystic and/or acne, accompanied by pain and cyst formation, with the total number of lesions exceeding 100 and more than 3 nodules or cysts.