Cappuccino has caffeine. Even decaffeinated cappuccino might contain caffeine. Since cappuccino is made with espresso, the amount of caffeine also depends on how many shots of espresso were used and how large the shots were.
According to the Mayo Clinic, 1 ounce of restaurant-style espresso has 47 to 75 milligrams of caffeine. One ounce of decaffeinated restaurant-style espresso can have from zero to 15 milligrams of caffeine.
Caffeine is a stimulant drug that comes in the form of bitter-tasting white crystals. In the case of espresso, cappuccino and other types of coffee, caffeine is found in the cherry of the coffee plant.
Caffeine works by binding with adenosine receptors in the central nervous system, which keeps the person awake. Caffeine also increases levels of epinephrine and also blocks the action of other neurotransmitters. It also causes blood vessels to narrow and causes the body to produce urine. It takes between 3 and 7 hours for half a dose of caffeine to clear the system of an adult.
Cappuccino is made when the shots of espresso are amended with steamed milk then topped with a cap of foamed hot milk. Some baristas also sprinkle curls of chocolate or ground cinnamon on top of the foam.