Dermatitis herpetiformis is a chronic skin condition characterized by itchy, blistering rashes. It is often associated with celiac disease, an autoimmune disorder triggered by gluten. The rash typically appears on the elbows, knees, and buttocks, and is caused by an abnormal immune response to gluten. Diagnosis usually involves a skin biopsy and blood tests for specific antibodies. Treatment focuses on a strict gluten-free diet, which can help alleviate symptoms and prevent future outbreaks. In some cases, medications like dapsone may be prescribed to reduce inflammation and itching.