When the back sunburn redness and pain, you can use saline, boric acid solution for wet compresses to reduce inflammation and pain, but also with loratadine and other drugs for treatment.
Skin for a long time in the sun under ultraviolet radiation, will lead to sunburn, back sunburn redness, swelling, pain, first of all to stop the ultraviolet radiation, to a cool place, the use of saline or boric acid solution for wet compresses, to reduce the local pain and inflammation, but also with Chlorotetracycline, cetirizine and other anti-allergy drugs for treatment.
Daily to avoid direct sunlight, do a good job of sunscreen, wear a hat, wear long-sleeved clothes, in addition to replenish the water, to prevent the body from dehydration caused by excessive heat.
If the symptoms are more serious, we suggest that you consult a dermatologist in a hospital and take the medication as prescribed by your doctor.