This Biotin is outstanding! I self-diagnosed myself with palmoplantar pustulosis (fortunately very mild for me). This manifests itself as small pustules under the skin on the palms of hands and soles of feet. After hours of research I found an article by a Japanese professor who claimed 100% successful cure using high-dose biotin. I can't get 5000 mg in the UK but I can in the USA. After a couple of weeks of using this once a day it has gone for good. Anyone with an unexplained skin condition or psoriasis should give this a go.