Must the water be warm to use the nasal rinse? Posted on January 1, 2019 by 0 Vote Up Vote Down Ask A Doctor Staff asked 4 years ago Must the water be warm to use the nasal rinse? 1 Answers 0 Vote Up Vote Down Ask A Doctor Staff answered 4 years ago Warming the(distilled, filtered [through 0.2 micron] or previously boiled) water to body temperature is for comfort only, and if you wish to use room temperature water, that is OK. Please login or Register to submit your answer Username or Email Address Password Remember Me