Drug info - Potentiation using Grapefruit Juice or Cimetidine

[crizzle]

So my understanding is that Cymetedine (Tagamet) potentiates the effects of opiates by the inhibition of the enzyme CYP2C6, while Grapefruit Juice potentiates the effects of opiates by the ihibition of the enzyme CYP3A4.

My question is, what is the difference? How does the inhibition of each enzyme uniquely potentiate the effects of opiates? Also, would the inhibition of both enzymes cause greater potentitation?

I have looked around and do not see this topic discussed yet, surprisingly.

crizzle added 9 Minutes and 36 Seconds later...

Wait, I just read this. This makes it look like GFJ inhibition of CYP2C6 is a myth and that both GFJ and cimetidine inhibit CYP3A4.


http://www.drugs-forum.com/forum/sho...ghlight=cyp2d6

I would really like to have some feedback regarding this. It seems like there still are many people that have the idea that GFJ inhibits CYP2C6 (including myself).