Never NOT have these bad boys in my cupboard. We take these at the first sight of any sniffle, cold and flu, and usually we would recover fairly quickly. It takes time for the body to adjust and "work with" these supplements. Don't expect miracles but consistency is key. Also I find taking them with meals is better and gentler on the stomach. Have tried different brands, so far I like this brand the most, because it seems to be more gentle on my stomach and work better.