the trial doc at cal pacific that is screening my friend said no grapefruit. I think she said no oj too, but I am not sure.
This is what Medhelp’s ex resident HCV expert, Dr. Dietrich, had to say about grapefruit and HCV therapy:
“It actually can increase some drug levels because of inhibiting a liver metabolic enyzme. However neither interferon or ribavirin is metabolized by that particular enzyme(p450) so it is OK to drink your grapefruit juice. Stay Healthy! DTD”
Interesting question, huh? It looks like discussions about grapefruit and ribavirin became especially common when those studies were published suggesting that naringenin in grapefruit can help block HCV replication. However, I think we still don't have a definite answer to this question. I did find a CHMP report on ribavirin in 2009, and it specified in inclusion/exclusion criteria (page 12) that "subjects were not allowed to consume grapefruit, Seville oranges and pomelo containing products for 14 days prior to period I dosing and throughout the study"... I wonder why...
Here is the source: http://www.ema.europa.eu/docs/en_GB/document_library/EPAR_-_Public_assessment_report/human/001064/WC500056848.pdf
Well, the single abstract I was able to find said that grapefruit contains purine molecules, which is apparently what Ribavirin turns into when it's metabolized. Apparently, this somehow hinders absorption of the Riba in the GI tract.
Here is the abstract: