Autoimmune progesterone dermatitis (APD) is a rare condition characterized by a cyclical cutaneous reaction to endogenous progesterone levels or as a reaction to exogenous progesterone. The clinical presentation is variable and commonly includes pruritic, urticarial, eczematous, vesiculobullous, or erythema multiforme-like mucocutaneous lesions. Less commonly reported presentations include features of fixed drug eruption, stomatitis, erythema annulare centrifugum, angioedema, and anaphylaxis. The lesions usually present 3-10 days prior to menses and remit shortly after the start of menstruation. This timeline corresponds with increased progesterone levels during the luteal phase of the menstrual cycle. The underlying mechanism of APD is unknown, but various theories exist. Multiple mechanisms are likely at play given the various clinical manifestations of APD. Proposed mechanisms include a type I IgE-mediated or type IV T cell-mediated hypersensitivity reaction to the patient's native progesterone, mast-cell activation, and immune complex deposition.

This condition tends to affect women between menarche and menopause but most commonly occurs in their third to fourth decade. It has been reported to occur in the postpartum period and in women undergoing in-vitro fertilization. It has also been reported in the case of a man taking synthetic progesterone. Cases have been reported to either improve or worsen during pregnancy.

Almost all patients experience pruritus. When urticaria predominates, it tends to be generalized in distribution and may be accompanied by laryngospasm. Anaphylaxis may occur. Oral erosions may also be present.

APD usually requires treatment, although the condition has been reported to have resolved spontaneously in several cases.