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Debbie L. · 10-04-2009, 04:42 PM

Being a good CYP2D6 metabolizer doesn't guarantee that Tamoxifen will be effective for an individual. But it's looking pretty sure that Tamoxifen does not do much for the other (much smaller) group - the poor metabolizers.

I've heard it said that one way to do this is just to take the Tamoxifen and see if you get side effects like hot flashes. If you do, you can be assured that you're a metabolizer. If not, maybe then it's worth getting tested, as there are many metabolizers who do not get side effects - the other way round (no se's) doesn't tell you anything for sure.

But this whole question is awaiting more evidence. That's why docs are slow to move on it - they're waiting for better information. That said, I don't really see a downside to doing the test, unless it's really expensive. Do you know how much it costs?

And while we're on the topic, there was one study (SABCS 08?) that found an association between response and se profile for AI's, also - although I don't think they have any idea what the mechanism would be there, as they do with the CYP2D6 theory for Tamoxifen.

Debbie Laxague

10-04-2009, 04:42 PM	#4
Debbie L. Senior Member Join Date: Jul 2006 Posts: 463	Re: Tamoxifen and CYP2D6 metabolizer Being a good CYP2D6 metabolizer doesn't guarantee that Tamoxifen will be effective for an individual. But it's looking pretty sure that Tamoxifen does not do much for the other (much smaller) group - the poor metabolizers. I've heard it said that one way to do this is just to take the Tamoxifen and see if you get side effects like hot flashes. If you do, you can be assured that you're a metabolizer. If not, maybe then it's worth getting tested, as there are many metabolizers who do not get side effects - the other way round (no se's) doesn't tell you anything for sure. But this whole question is awaiting more evidence. That's why docs are slow to move on it - they're waiting for better information. That said, I don't really see a downside to doing the test, unless it's really expensive. Do you know how much it costs? And while we're on the topic, there was one study (SABCS 08?) that found an association between response and se profile for AI's, also - although I don't think they have any idea what the mechanism would be there, as they do with the CYP2D6 theory for Tamoxifen. Debbie Laxague