I started taking this product once per day as part of a recommended immune boosting protocol. I have asthma and noticed that the Quercetin was giving me relief from some of my asthma symptoms., but that the relief only lasted half a day. So I checked the dosage on the bottle...it said I could take two capsules per day...so I started taking one every 12 hours. I'm pleased to report that I am coughing less, the reduction in Ventolin is quite noticeable, I'm sleeping better and that distracted/anxious feeling you get when your breathing isn't right and nothing seems to help...is all but gone. I've only been doing the double dose for a week...but I must say, so far, I am impressed.