I sold a product several years ago called "Defense" by Brain-Twist, Inc. (16oz. cans)
Defense Effervescent Supplement | BevNET.com Product Review + Ordering
It was more of a novelty, sold a bit when first introduced but not many repeat orders. It was sold as a functional beverage with taste being below average. If I remember correctly the beverage was carbonated, when opened the small plastic powder container inside would burst open and the beverage would take a minute or so to mix. I don't see it around anymore. Stores always wanted to place it in the energy section because it had the look of a 16oz. energy drink, confusing to consumers.