This medicated shampoo was designed to reduce dandruff, but doctors noticed hair regrowth in some patients using it. Studies proved it, and so a new hair regrowth product was found. Nizoral can remove excess sebum and is soothing to the scalp, reducing androgens and inflammation. This hair regrowth shampoo may sting the scalp, so is best used every second day. Don’t use it too often, since ketoconazole can damage some people’s hair.