I don't know how this product does the work but it does work wonders! I never had any dandruff problems until I moved from Philippines to Chicago. Maybe the extreme change of environment caused my dandruff. My scalp was so dry and flakey and there's dandruff everywhere. I looked for a product that can help me and I saw Nizoral and many swear by it so I gave it a try. After 3 uses, I still have dandruff but the moisture in my scalp is slowly going back. After 5 uses, dandruff has been reduced to about 50% (based on feeling). After 12 uses, dandruff is completely gone. I'm planning to buy more of this and send it to my friends in the Philippines who suffer from extreme dandruff. I swear by this product!