A scalp sore is a sore, bump or blister on the scalp, as stated by Fitness Health 101. Scalp sores can develop due to acne, allergic skin reaction, or an infection of the hair shafts, reports eMedicineHealth.
Over-the-counter treatments for many scalp sores are effective, states Fitness Health 101. Folliculitis, which is caused by irritation of the hair follicles in individuals with high hair density, is an example of a more severe scalp condition that results in scalp sores. Scalp psoriasis, a chronic disease that flares and subsides and that is usually genetic, can also cause scalp sores. Topical treatments relieve these conditions once a medical professional diagnoses them.