Have you had risky sex recently? If no then I would treat this like a rash or skin irritation. Make sure the area is cleaned gently and dry. You may try skin ointment with Cortisone that is designed for sensitive skin maybe something from the baby aisle. Per WebMD. This medication is used to treat a variety of skin conditions (e.g., insect bites, poison oak/ivy, eczema, dermatitis, allergies, rash, itching of the outer female genitals, anal itching). Hydrocortisone reduces the swelling, itching, and redness that can occur in these types of conditions. This medication is a mild corticosteroid.