I have heard this about the tonic water w/quinine, but have not done extensive research on it. I've heard a lot of anecdote but not read a lot additional on the topic. And yes, I do believe that the same enzyme with which GFJ interferes is associated with metabolization of steroidal compounds is the same one associated with the metabolism of opiates. I don't know how much more we can talk on those lines in this section of the forum, but on a purely scientific plane you're correct.
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