Tarsum is the only therapeutic shampoo designed to be applied before bathing. Its special applicator cap allows you to put Tarsum directly on psoriasis plaques. You treat your scalp, not your hair! Every other therapeutic shampoo requires you to dilute the medication and stand around the shower with a headful of lather to receive treatment. Applying Tarsum directly to the scalp before bathing allows you: Apply full strength, undiluted treatment exactly where you need it most. Better control over the amount of time you treat your scalp.