tl;dr: "5 hour energy", as well as Costco's generic version thereof, contain a megadose of vitamin B6 which is not safe for daily consumption. The lesson you s

tl;dr: "5 hour energy", as well as Costco's generic version thereof, contain a megadose of vitamin B6 which is not safe for daily consumption. The lesson you should take from this is that, when taking a combination drug like an energy drink, you have to go through ingredient by ingredient checking the dosages and reading the corresponding wikipedia pages. I do consume energy drinks, but I used that procedure to reject the brand that's reported causing a problem here.