The rash, as the name implies, is caused by drugs and is also known as drug dermatitis, which cannot be discharged and can only fade properly. The most common external use is contact dermatitis, the most common safflower oil, flower lotion can cause contact dermatitis, you can use external boric acid solution wet compresses to let it slowly fade. More drug rash mainly refers to the internal, lighter called fixed erythema, only a long erythema, some cases without taking drugs will subside on their own, many patients will take drugs after the erythema, hives, itchy rash, will also be self-relieved, the drug in the body after 1-2 days, not more than a week can be completely metabolized. In the later stages of drug rash, such as mild itching, will be relieved quickly if you do not continue to take allergic drugs and there is no further stimulation. If not, the rash will also subside quickly by taking anti-allergy medication. More persistent drug rashes, such as severe erythema multiforme, need to be treated in a hospital and are quite serious cases.