 [ Symptoms ] i have been using medicated head & shoulders for seborrheic dermatitis for almost a year now should i keep using it  very itchy scalp with oily dandruff [ Disease ] head and shoulders is primarily zinc you may want to try a shampoo that contains selenium selsun blue make sure to read the label since some do not contain the selenium you can also ask your medical provider for a prescription selenium containing shampoo to use