Although endogenous or exogenous exposure to progesterone or estrogen that induce a spectrum of hypersensitivity reactions and/or other skin eruptions are believed to be uncommon, their prevalence is currently unknown. Clinical manifestations are heterogeneous but typically involve cyclical manifestation of a spectrum of dermatitis conditions and/or systemic symptoms. Diagnosis is made primarily by history in conjunction with in vitro assays to measure specific IgE and provocation challenge testing when appropriate; judicious use of skin testing is recommended because of their irritant-causing effects. Pathomechanisms are incompletely understood but likely involve IgE-mediated immediate-type hypersensitivity. Treatment is aimed at symptomatic control with nonsedating histamine 1 antihistamines, short-term use of systemic glucocorticoids, progesterone desensitization, and/or suppression of ovulation by a pharmacologic or, as a last resort, surgical approach. Instructions Credit can now be obtained, free for a limited time, by reading the review article and completing all activity components. Please note the instructions listed below: Review the target audience, learning objectives and all disclosures. Complete the pre-test. Read the article and reflect on all content as to how it may be applicable to your practice. Complete the post-test/evaluation and claim credit earned. At this time, physicians will have earned up to 1.0 AMA PRA Category 1 Credit TM. Minimum passing score on the post-test is 70%. Overall Purpose Participants will be able to demonstrate increased knowledge of the clinical treatment of allergy/asthma/immunology and how new information can be applied to their own practices.