If acne suddenly becomes big and painful, it is considered to be caused by inflammation or local infection, according to the degree of infection of acne, those without obvious infection symptoms can take anti-inflammatory drugs, and those with obvious infection need to be drained, take antibiotics and surgical treatment. 1. No obvious symptoms of infection: acne suddenly becomes big and painful, there is no symptom of redness and swelling of the surrounding skin, there is no obvious symptom of infection, try not to squeeze and stimulate with hands, you can take anti-inflammatory drugs such as cefaclor to relieve the pain, and pay attention to keep clean in order to avoid recurrence, which will lead to aggravation of the symptom. 2. Obvious symptoms of infection: acne suddenly becomes big and painful, accompanied by obvious fluctuating sensation locally, obvious symptoms of infection, accompanied by pus outflow, need to drain, clean up the pus and necrotic tissues, and take antibiotic medicines such as cefdinir and levofloxacin under the guidance of doctor, and then undergo surgery for radical excision after the inflammation subsides. Powder tumors suddenly become large and painful, it is recommended to actively seek medical attention, after a clear diagnosis for treatment, specific medication should be under the guidance of a physician.