Sudden breakouts may be caused by acne, folliculitis and other diseases. 1. Acne: The cause may be related to heredity, increased sebum secretion, abnormal keratinization of sebaceous gland ducts in hair follicles and inflammatory reactions. Patients will have pimples, pustules and other symptoms, which can be seen on the face, chest and back and other areas. Endocrine, emotional and dietary factors can induce aggravation, resulting in sudden acne breakouts. 2. Folliculitis: the cause of the disease is mainly related to pathogenic bacterial infections, common staphylococcus aureus, malassezia, etc. Wearing tight clothes, sweating, shaving and other reasons may also induce the disease. Patients will have localized red papules, usually centered on hair follicles, which tend to develop into pustules and may be accompanied by itching and pain. If sudden acne breakouts occur, it is recommended to go to a regular hospital for examination to clarify the cause of the disease.