Hello Miss, Welcome to HCM, From your history its most probably seems Autoimmune progesterone dermatitis (APD). It is a rare skin condition in women that recurs in a cyclical manner corresponding to their menstrual cycles. It is thought to be a response of the skin to the hormonal changes that happen just before menses. Characteristically, the skin eruptions occur during the luteal phase or the late pre-menstrual phase of the cycle. This is when the blood level of the sex-hormone progesterone rises. The skin rash happens as an autoimmune response to the body s own progesterone, hence its name. Within a few days of menstruation when progesterone level falls, there is partial to complete resolution of the rash. It will recur during the next cycle. Some patients have had previous exposure to external progesterone in the form of oral contraceptive pills. This is thought to pre-sensitize patients to react against their own internal progesterone. However, not all patients with APD are exposed to previous hormone therapy. It has been postulated that these patients produce an altered form of progesterone that incites an immunologic response against it. In another theory, progesterone is thought to heighten a patient s hypersensitivity response to another allergen. How does progesterone dermatitis present? A variety of rashes has been described. The most common are urticaria and erythema multiforme. Other presentations include: Papulovesicles (eczema-like) Annular erythema Angioedema Mouth erosions (stomatitis and aphthous ulcers) Itch (the most common complaint) Several other skin conditions may be more severe during the perimenstrual period, but these are not classified as autoimmune progesterone dermatitis. These include: Herpes simplex infection (cold sores) Acne and seborrhoea Rosacea Atopic dermatitis Contact allergy to nickel Lupus erythematosus Psoriasis On average, the skin rash happens 7 days before onset of menstruation and lasts for 1-3 days after menstruation. The age of onset is variable, the youngest case occurred at menarche and the disease can begin as late as 48 years of age. Autoimmune progesterone dermatitis Image provided by Sharon Morton Autoimmune progesterone dermatitis How is progesterone dermatitis diagnosed? The diagnosis is usually made from the characteristic cyclical presentation. A skin-prick test with intradermal progesterone is helpful. Positive tests with progesterone can be fairly rapid, usually developing as urticaria within 30 minutes of inoculation, or delayed with rashes peaking at 24-48 hours. Provocative testing with intramuscular or oral progesterone can be performed as an alternative. Skin biopsy alone is seldom diagnostic. A variety of histological features have been described. Superficial perivascular mixed inflammation is the most consistent finding. How is progesterone dermatitis treated? If the skin problem is mild, it may improve with topical steroids (for eczema) and antihistamines (for urticaria). Severe disease may be treated with systemic corticosteroids. The production of progesterone can be suppressed with hormone-based therapy. This includes the use of conjugated oestrogen (American spelling estrogen), ethinyl oestradiol (estradiol), tamoxifen and danazol. Women with autoimmune progesterone dermatitis should try to avoid medications containing progesterone including the combined oral contraceptive pill, minipill, depo injections. The specific drugs to avoid include norethindrone, norgestrel, levonorgestrel. I hope this helps..Dr.Satyam Bhavsar (MBBS,India) :)