Rockstar® Energy Drink Blackout. Guarana. B-Vitamins. Taurine. Caffeine. 240 Calories per can. 16 fl oz (473 ml). Total caffeine from all sources: 160mg per can. In each serving: Taurine 100mg, guarana seed extract 100mg, caffeine 80mg, glucuronolactone 50mg, L-carnitine 25mg, Inositol 25mg. Visit: www.rockstarenergy.com. ©2016.