Why is taking something like fioricet make my head feel a bit better,?

Why is taking something like fioricet make my head feel a bit better,?
not 100%, but causes rebound All kinds of Headache…?

There are losts of good answers, but the best answer:

Answer by izzy
Overuse or misuse of pain relievers can cause you to “rebound” into another headache.
Pain relievers that contain a combination of caffeine, aspirin and acetaminophen (Excedrin, others) are common culprits. This group also includes prescription medications such as Fioricet.
Some combination medications have even been withdrawn from the market in certain European countries.
We can’t get floricet in UK.

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