How long does it take for fioricet (acetaminophen butalbital and caffeine) to leave your system? is it good for long term migraines?

Limit use of Fiorcet: Fioricet (acetaminophen butalbital and caffeine) is a combination drug of butalbital (a barbiturate) acetaminophen, (aspirin) and caffeine. Affective for tension headache; however, the barbiturate could cause euphoria, drowsiness, intoxicated feeling and light- headedness. Must utilize in a cautious manner. Habit forming and overuse could extenuate symptoms. Butalbital has a half life of 36-38 hrs. Better to use short term; spec. rxs.

1 day: The half-life of Fioricet (acetaminophen butalbital and caffeine) is approximately 4 hours. That's means the time it takes the blood to eliminate half of the drug is 4 hours. It takes approximately 6 half lives for a drug to be eliminated from your system. 4*6/24= 1 day. It is not clear if Fioricet (acetaminophen butalbital and caffeine) should be used for treating migraines