Choose your own mix from all six flavors: Grapefruit, Blueberry, Citrus Tea, Raspberry Pomegranate, Ginger Blood Orange, and Kiwi Strawberry. Pick your flavors on our site; if you order without choosing, you'll receive an even mix of all six.

The CircaFLOW™ blend pairs a solid 225mg of caffeine with Dynamine™ and TeaCrine® for a layered release of energy. Dynamine™ comes on first, caffeine carries the middle of your shift, and TeaCrine® extends the tail so the energy tapers instead of dropping off. Completing the blend: L-theanine, tyrosine, taurine, ginseng, inositol, adaptogenic mushrooms, huperzine A, and B vitamins. Zero sugar, 10 calories per can.

Created by Dr. Thomas Jeider, an ER physician who has worked nights since 2010.

Six 12 fl oz cans, $4.29 a can, shipping included. Subscribe and save. Order by 2 p.m. Eastern and it ships the same day (Mon to Fri).