9 replies to this topic

[KimberCT]

I saw that Piperine and Quercetin were inhibitors of CYP3A4, which is one of the liver enzymes that metabolizes Escitalopram (Lexapro) along with CYP2C19.

My Vitamin C supplement contains Quercetin and my Curcumin supplement contains Piperine.

Can anyone recommend a course of action?

Should I eliminate these from my supplement intake... take them AM and Lexapro PM... or simply not worry about the amount of inhibition these cause?

Edited by KimberCT, 10 June 2009 - 08:33 PM.

[StrangeAeons]

definitely worry about the quercetin; piperine I'm not as sure of. I would get rid of the supps; it's far more important that you take the medication in the appropriate dosage. Messing with the elimination of your medication makes it more difficult to gauge its effectiveness, and less likely to maintain stable levels in your bloodstream. By and large if there's a conflict between a prescription medication and a supplement, drop the supplement.

[ajnast4r]

Can anyone recommend a course of action?

piperine has significant effects on cyotochromes.

dump it and buy plain vitamin C.

[nameless]

How much quercetin would it take to affect liver enzymes? I ask, as sometimes vitamin makers just put token amounts in their supplements for label purposes How much is in your Vit C supplement?


If your vitamin C has less quercetin than... say, several bites of an apple, not so sure how it would cause a problem really. You probably already consume some quercetin via diet. But if it's a large amount, then yeah, probably a good idea to drop it.

Edited by nameless, 10 June 2009 - 10:55 PM.

[niner]

I would not worry about the quercetin at all. Quercetin is a fairly weak inhibitor of 3A4; for example, the IC50 for the quercetin inhibition of the 3A4 oxidation of nifedipine is 80 uM. You are NEVER going to see that kind of concentration in vivo. In fact, our diets are full of quercetin from a variety of foods. Our bodies have a well developed way of getting rid of quercetin; we conjugate the hell out of it and eliminate it easily, just like we do with resveratrol.

The curcumin/piperine combination might be slightly more of a concern. I've seen reported Ki's of piperine against CYP3A, depending on the substrate, of between 5 and 77 uM. IF the 3A4 oxidation of Lexapro is at the low end of that range, AND piperine has great pharmacokinetics, then it might have some effect, probably small, on Lexapro levels. The curcumin is also a bit of an issue as well, in that curcuminoids inhibit CYP2C19 modestly.

If the curcumin/piperine combo isn't important to you, and you want to be super safe, just drop it. If you like the curcumin/piperine, and you have some idea of what a Lexapro overdose feels like, then just watch for it. If you don't see it in a few days, it's not going to be a problem. A Lexapro OD might feel slightly trippy or it might give you a wonderful feeling of energy. That would be a hypomania. If you find yourself saying I feel GrrrrrrEAT! like Tony the Tiger, then you probably are hypomanic from too much Lexapro. IMHO, this is not likely to occur.

Don't worry about the quercetin.

[KimberCT]

Thanks for the advise everyone.

Here's what my intake would look like...

(T) - 250mg Quercetin, 10mg Piperine
(T + 5h) - 250mg Quercetin, 10mg Piperine
(T + 10h) - 250mg Quercetin, 10mg Piperine
(T + 15h) - 10mg Lexapro

If Quercetin/Piperine primarily inhibits first pass metabolism only, I'm hoping the 5 hour gap before I take the Lexapro may negate most of it?

Right now, I'm holding off on everything until I do more research.

Edited by KimberCT, 11 June 2009 - 02:12 PM.

[StrangeAeons]

well, guess you learn something new everyday; I don't know why I thought quercetin was a strong inhibitor of 3A4. Thanks for your expertise, niner, and clearing the air. I retract my previous post. Probably should start studying organic chem.

[ajnast4r]

Thanks for the advise everyone.

Here's what my intake would look like...

(T) - 250mg Quercetin, 10mg Piperine
(T + 5h) - 250mg Quercetin, 10mg Piperine
(T + 10h) - 250mg Quercetin, 10mg Piperine
(T + 15h) - 10mg Lexapro

If Quercetin/Piperine primarily inhibits first pass metabolism only, I'm hoping the 5 hour gap before I take the Lexapro may negate most of it?

Right now, I'm holding off on everything until I do more research.

thats too much piperine for daily intake imo. why are you even taking piperine? to potentate the quercetin or vitamin C?

[KimberCT]

Thanks for the advise everyone.

Here's what my intake would look like...

(T) - 250mg Quercetin, 10mg Piperine
(T + 5h) - 250mg Quercetin, 10mg Piperine
(T + 10h) - 250mg Quercetin, 10mg Piperine
(T + 15h) - 10mg Lexapro

If Quercetin/Piperine primarily inhibits first pass metabolism only, I'm hoping the 5 hour gap before I take the Lexapro may negate most of it?

Right now, I'm holding off on everything until I do more research.

thats too much piperine for daily intake imo. why are you even taking piperine? to potentate the quercetin or vitamin C?

Neither.  I originally ordered the piperine containing supplements to potentiate curcumin, CoQ10, and resveratrol which I would take at the same time.

My Vitamin C supplement, which I was already taking 3x a day on the above schedule, just happened to contain 250mg of quercetin per capsule.  I wasn't even aware it was a CYP3A4 inhibitor until I started researching piperine.

[ajnast4r]

...

imo, the supplements you mentioned are absorbed just fine and piperine is not needed. there have been some in depth discussion on the detriments of higher piperine intake here. with the highest safety in mind, you should probably stop taking piperine.