Years of tattoos suddenly itchy and bulging, if it is an allergic reaction, you can use topical glucocorticoid ointment; if it is a scar hyperplasia, it can be closed locally or take surgery; if it is a bacterial infection you can use antibiotic ointment, incision and drainage and other methods. 1. Allergic reaction: contact dermatitis, urticaria and other allergic reactions, may lead to tattoo suddenly itchy bulge. You can use compound dexamethasone ointment, tretinoin cream externally; severe itching, with the taking of loratadine, cetirizine and other drugs. 2. Keloid hyperplasia: Years of tattooing may cause localized keloid hyperplasia, which may also lead to sudden itching and bulging of the tattoo. You can local injection of tretinoin suspension and other drugs for local closure, and in serious cases, surgical treatment is needed. 3. bacterial infection: bacterial infection caused by localized folliculitis, boils and other inflammatory reactions, may also lead to sudden itching and bulging, and external mupirocin ointment, erythromycin ointment and other antibiotic drugs, if the formation of abscess can be discharged, you can be treated through incision and drainage and other measures. The above symptoms are recommended to go to the hospital for examination, to clarify the cause of the disease, and standardized treatment under the guidance of the doctor. Drugs should be used in accordance with the doctor’s instructions, do not self-medication.