Alpecin Double Effect Shampoo fights against dandruff & hair loss hereditary with caffeine complex. In the first step, this Double Effect Shampoo loosens scaly, keratinous cells & thoroughly removes dandruff from the scalp. This clears the way for the caffeine complex. In the second step, the active ingredients penetrate into the hair root & strengthen it against hereditary hair loss. Leave the product on the scalp for two minutes- from application to rinse.