Caffeine in pain relief drugs?

Why is caffeine added in many pain relief drugs? Some websites say that caffeine increases the effect of the drug, but how?

Caffeine is a metabolism stimulant, and it will actually make you absorb the medication faster.

Thats basically all there is to it. Nothing complicated really. Report It

Here is a good link that will answer your question or any other drug question you may have.

http://www.pdrhealth.com/home/home.aspx