I've been drinking kava daily for 6 months now and find that I can't drink coffee any more. It keeps me jittery and awake for 14 or more hours. In fact, I'm awake right now because of coffee I drank this morning. I Googled this and found
that kava inhibits the CYP1A2 enzyme which is
responsible for metabolizing caffeine. So my question is, does anyone else have increased sensitivity to caffeine since they started drinking kava?
(Several more enzymes are affected according to the first link, for instance CYP2C9 which metabolizes ibuprofen and other drugs. They're listed in the first link and are interesting to examine. Kava could in fact affect the metabolism of hundreds of drugs and might be worth mentioning during your visits to the doctor.
)
Cheers!