So... a little update... the daily recommended dose of biotin for adults is 30 mcg/day. I was consuming my regular multivitamin PLUS 10,000 mcg of bioton /day... 5,000 in the AM and 5,000 in the PM... when I stopped taking it, it took about 3 days to stop getting the hives, but I stopped getting the hives. As soon as I'm able, I will make an appointment with a dermatologist. However, I'm pretty sure it was the OVERDOSE of biotin. I was taking it because I'm afraid of the hair loss, but obviously, TEN THOUSAND micro-grams a day is just too much.