Nizoral Shampoo kills the fungus at the root of the problem! Scientists confirm that dandruff, seborrhea and associated dry scalp can be caused by microscopic fungus that occurs naturally on everyone's skin, called Pityrosporum ovale. Given the right conditions (stress, changes in diet or climate), the fungus can grow more quickly resulting in dandruff. Clinically proven Nizoral helps maintain a healthy scalp with the anti-dandruff shampoo that kills dandruff & controls itchiness & flaking. A soft shampoo with ketoconazole, use it twice a week between shampoos for a flake-free scalp