Hi Dear , Welcome to HCM. Understanding your concern. As per your query symptom such as dryness and swelling/ blistering of lips are pointing towards to condition an allergic reaction or infection. The allergic reaction can occur due to various reasons like food allergy, allergy from tooth paste or other dental product or excessive exposure to sun . Infection can be bacterial or viral. I would suggest you to take over the counter antihistamine drug like benadryl ,keep your lip moist by applying lip balm containing broad spectrum sunscreen stop using any product on face or inside mouth if you start it recently and apply clove oil at night . If condition still persist then consult dermatologist for proper examination and to rule out any other underlying disease. Doctor may order blood test and prescribe topical/oral antibiotics/antiviral depending upon the condition and topical steroid. Hope your concern has been resolved. Get Well Soon. Best Wishes, Dr. Harry Maheshwari