I have purchased these Zinc Lozenges twice now. After using them as prescribed the first time, and having them work, I was sold! My husband recently caught something after traveling. He chose to take an over the counter infusion of vitamin treatment. I, on the other hand, immediately began taking the Advanced Zinc Lozenges as prescribed and even though he had it for 10 days, I felt very minor signs. It is truly amazing how well these work but the key is to take them as prescribed, even though you may get tired of taking as often as you need to. For a zinc lozenge, the taste is not bad at all either.