No, biotin is mainly a vitamin and most vitamins have minimal effect or impact on dihydrotesterone. That being said, what biotin does is create a specific set of optimum conditions that allows fast and healthy blooming of hair. To some extent, this can stop hair loss at its tracks especially when combined with known blockers and inhibitors of dihydrotestosterone. Also, a combination of vitamin D and biotin has been shown to be relatively effective at halting hair loss and regrowing bald patches in some people.