A breakout period does not necessarily occur after taking isotretinoin. If a breakout period occurs, it usually occurs 2-4 weeks after taking the medication and can be recovered in 1-2 weeks. Isotretinoin is a prescription medication generally used for refractory nodular acne where conventional systemic antibiotic therapy has failed to treat acne. It can treat acne by reducing sebum secretion by shrinking sebaceous gland tissue, reducing keratinization of epithelial cells and keratin plugging at the mouth of follicular sebaceous glands, and inhibiting the growth of Propionibacterium acnes. In general, whether a period of acne breakout occurs after taking isotretinoin depends mainly on the patient’s constitution and endocrine situation. Patients with acne breakout usually appear 2-4 weeks after using the drug and disappear in 1-2 weeks under normal circumstances; if there is no relief or even aggravation of acne breakout, the drug should be discontinued immediately and promptly seek medical treatment. In addition, because isotretinoin has more side effects and can have an effect on various systems in the body, it is prohibited for women during pregnancy or in the preparation of pregnancy, otherwise it can be teratogenic, and pregnancy can only occur 3 months after stopping the drug.