Dr. Jessica J. Krant, a board-certified dermatologist at the Laser & Skin Surgery Center of New York, has heard of this happening, too. “Many reports indicate that excess ingested biotin can lead to rashes and acne breakouts,” she said. “There are no real scientific, blinded, placebo-controlled research trials to prove this, but if you start taking biotin and get worsening of your acne, the biotin may indeed be the culprit.”.