Fess Sinu-Cleanse Isotonic Wash is a gentle, non-medicated isotonic wash that helps relive nasal and sinus congestion. Fess Sinu-Cleanse Isotonic Wash is an isotonic saline solution that has a lower salt concentration and is ideal for washing and daily cleansing of the nasal and sinus cavities. Daily use post-operatively will help clear the nasal and sinus cavities of dried blood and mucus. Fess Sinu-Cleanse Isotonic Wash contains Xylitol that helps guard against bacteria.