Flo Sinus Care is a gentle yet effective sinus irrigation or wash kit designed to relieve congestion which may be a result of: Sinus congestion Hayfever & Allergies Flo Sinus Care is a non-medicated, preservative-free, isotonic irrigation solution for washing the nasal passages and sinus cavities. It’s gentle to use and helps thin and wash away excess mucus and clear airborne irritants to relieve congestion in both the nose and sinus.