Buy Fioricet Online is a prescription-only combination medication. It is made up of acetaminophen, butalbital, and caffeine, and each of these substances serves a specific purpose in its own right. Fioricet contains 50 milligrams of Butalbital, 500 milligrams of Acetaminophen, and 40 milligrams of Caffeine in each dose. The food and drug administration (FDA) gave it the all-clear in 1984.