Question for Bryan: Grapefruit Juice

[htownballa]

Bryan,

Will taking grapefruit juice daily with propecia to increase absorption into bloodstream result in upregulation of the enzymes that metabolize the propecia (and various other substances)?

My concern is that if i use grapefruit juice i may become "dependent" on it

Thanks

 

[htownballa]

bump

 

[bubka]

what would grapefruit have to do with finasteride absorption?

finasteride has on food interactions

 

[htownballa]

what would grapefruit have to do with finasteride absorption?

finasteride has on food interactions

Grapefruit juice has been scientifically proven to inhibit the activity of cyp3a4 enzymes in the small intestine. These enzymes metabolize finasteride thereby decreasing absorption into the bloodstream. So if u take grapefruit juice with ur finasteride tablet u shud get a larger dosage in effect. Its the dependency issue that i am worried about.

 

[Bryan]

Bryan,

Will taking grapefruit juice daily with propecia to increase absorption into bloodstream result in upregulation of the enzymes that metabolize the propecia (and various other substances)?

I can't give an absolutely definitive answer to that, but I will say that I've never heard of the production of any of the cytochrome P450 enzymes (including the CYP3A4 subgroup) being under any kind of feedback control. In other words, I haven't heard that there is any kind of system which sort of "monitors" the levels of those enzymes, and automatically upregulates their production if it finds them being depleted for some reason. For that reason, I think it's rather unlikely that drinking grapefruit juice to improve the absorption of finasteride will in any way "upregulate" the production of extra CYP3A4 enzyme. But if I'm wrong, I'm wrong! :wink:

My concern is that if i use grapefruit juice i may become "dependent" on it

I don't understand what you mean. "Dependent" in exactly what sense? Surely you don't think that using grapefruit juice even temporarily would have a PERMANENT effect on the way your finasteride is metabolized, do you??

Bryan

 

[htownballa]

Thanks a lot for the reply Bryan.

By dependent I meant that once I stop taking the grapefruit juice, my 1mg of finasteride will become useless due to massive metabolization in the intestine. I dont mean it would effect the metabolization of finasteride FOREVER, but for a while until the enzyme levels get back to normal. This would obviously be counterproductive to me. Of course this would only occur if the cyp3a4 enzymes are upregulated at all. I get the feeling that most things in the body are under some sort of a feedback control system, so taking propecia with grapefruit juice might be bad in the long run (unless u take grapefruit juice with it forever)

Or maybe Im overthinking this way too much lol

 

[htownballa]

Bumped

 

[Thinning]

If you are worried about it that much, dont do it.