NCIt definition : A combination preparation of acetaminophen, butalbital, and caffeine. Acetaminophen
exerts antipyretic and analgesic activities by inhibiting prostaglandin synthesis.
Butalbital, a barbiturate with an intermediate duration of action, depresses the central
nervous system and exerts sedative activity. Caffeine is a central nervous system
stimulant and causes constriction of dilated cerebral blood vessels. This combination
is used for the relief and treatment of migraine and tension headaches.;