Berocca Boost Effervescent Tablets contain caffeine, designed to give you a little kick exactly when you need it. As with every Berocca product, Berocca Boost contains all eight B vitamins along with magnesium, zinc and vitamin C. However, Boost also contains the natural herb guarana and, thanks to the caffeine in each effervescent tablet, Berocca Boost is great for helping to improve your alertness and concentration when you need it most.