Use this if you have a cold - the study at UCLA showed that if you use zicam at the very first sign of a cold you can reduce the duration of the cold by about 2-3 days. But you have to use it every 2 hours and really be consistent with it. And, you have to start almost immediately at the first signs and symptoms. I have recommended this product to all of my patients and friends throughout the years. Get the one that is zinc based and meant for colds.