Pemphigus is a group of rare skin disorders that cause blisters and sores on the skin or mucous membranes, such as in the mouth or on the genitals.

The two main types are pemphigus vulgaris and pemphigus foliaceus. Pemphigus vulgaris usually starts in your mouth. It can be painful. Pemphigus foliaceus affects the skin and tends to be more itchy than painful. Pemphigus can occur at any age, but it's most often seen in people who are middle-aged or older.

Pemphigus is not to be confused with bullous pemphigoid, another blistering skin condition. Usually a chronic condition, pemphigus is best controlled by early diagnosis and treatment. Treatment may include medications and therapies similar to those used for severe burns.