Hi Dear , As per your query you have red, raised, burn like rash on arm , which is like soft leather and not sore to touch . Well there can be many reasons for symptoms you mention in query like contact dermatitisis caused by an adverse reaction to something that touches the skin, including chemicals found in detergent, soap or a fragrance , exposure to certain plants, such as poison oak or ivy, an animal bite, or an insect sting , lyme disease and rocky Mountain spotted fever is another tick-borne condition . I would suggest you to clean the affected area with old water and mild soap , apply petroleum jelly , take bandryl twice a day and prevent it from sun exposure . If condition doesn t get better then consult dermatologist for proper examination . Doctor will take history , examine physically , order skin patch test and allergy test . Doctor may prescribe corticosteroid ointment , immunosuppressants , anti inflammatory and antibiotics . Hope your concern has been resolved. Get Well Soon. Best Wishes, Dr. Harry Maheshwari