Rx cream. I like silvadene (silver sulfadiazine) cream. It is an antibiotic cream with soothing effect. It requires prescription so see a doctor. If the wound is already healing, try Hydrocortisone cream.
Many possibilities. There are many types and causes of skin rashes that could cause itching. Several types of inflammatory conditions of the skin, allergic reactions, and sometimes bacterial, viral or fungal infections can cause rashes on the skin. Insect bites can also be the cause of a rash on the skin. Have it evaluated by a professional and get the appropriate treatment.