I've been using this product for years with great results. It's worked especially well this year to prevent me from catching any of the flu bugs going around.
I take anywhere from 2 to 6 per day depending on how tired I feel. Two at night right before bed works well when I know I'm not going to get much sleep. I don't recommend taking the maximum dosage right away. One capsule 2-3 times a day works fine when first starting.