Right chest and back, if there are red spots accompanied by itchy skin, it is considered to be an allergic rash, you can use topical glucocorticoids to control allergies such as dinexidine cream, dexamethasone cream, etc.; if the red spots are painful, it is considered to be a viral infection, it is recommended that oral and topical antiviral medications be used to treat the problem, and the commonly used antiviral drugs include acyclovir ointment and famciclovir capsules. 1. If it is caused by allergy, such as contact dermatitis. Clinical manifestations are mainly erythema, itching, this situation suggests drug treatment, oral anti-allergy drugs such as loratadine, cetirizine, etc., topical anti-glucocorticoid such as dianabed ointment, dexamethasone ointment and so on. 2. If it is caused by viral infection, such as herpes zoster. Clinical manifestations of band-like distribution of erythema, blisters, accompanied by neuralgia, treatment can be oral antiviral drugs such as acyclovir, painkillers such as pregabalin, nutritive nerves such as methylcobalamin, etc., and the joint use of topical acyclovir cream and other drugs. There may be other causes of erythema on the right chest and back, it is recommended to go to the hospital in a timely manner to identify the cause, symptomatic treatment, medication should be used in accordance with medical advice.