I Had An Itchy Welty Red Rash, How To Get Rid Of It ?

I am a retired 55 year old female and my husband and i lived in a boarding house with 20 men in sydney australia. it was shared bathroom/kitchen. i had an itchy welty red rash that at first appeared as a ring. location: right side crotch near the labia. treated with liquid 1% tolnaftate. i traveled back to florida with this problem. one week passed and it was more inflammed and itchy. switched to benedryl cream and 1 benedryl tablet at pm and the welts subsided. crotch skin still dark red patch, no distinct ring. however, same rash (without forming a ring) has formed on both elbows, right upper buttocks , back of hands, side of armpits. the elbows and buttocks are very inflammed. this has been 2 1/2weeks since the first eruption. treatment is benedryl cream and tablet and is not reducing the welts/itch. my husband does not have this and we are monogamous and sexually active. i am stressed with mother in nursing home and prospects of disposing of her condo and her possessions.