Dermatitis herpetiformis (DH) is a chronic, autoimmune, itchy blistering disease associated with gluten sensitivity. It is caused by an immune reaction to eating gluten, a protein found in some grains, including wheat, rye, and barley. The majority of people with DH have celiac disease, an illness in which the small intestine is damaged by the immune reaction to eating gluten. DH affects 10-15% of people with celiac disease and is more common in men. It is characterized by intensely itchy blisters filled with a watery fluid. The rash usually presents on the elbows, knees, shoulders, buttocks, or scalp when gluten-containing foods are consumed. The immune system in the small intestine reacts to gluten and produces antibodies that travel through the bloodstream and build up under the skin, causing the rash. Sometimes a gluten-free diet is the only necessary treatment for DH; however, steroid creams may be prescribed to speed resolution. There is no cure for DH, and symptoms may come and go. The best way to prevent and reduce symptoms is by maintaining a gluten-free diet continuously.