metabolizing tamoxifen?

Sunflower64

metabolizing tamoxifen?

Sunflower64

hi girls,

i talked to my onco about that cypd test for metabolizing tamoxifen. she said i will know if the tamoxifen is working if you are having hot flashes. i do have hot flashes but they are nothing severe. they are more like a rush of warmth through my body, no sweating. so my question is do the hot flashes have to be severe and wet if you are a good metabolizer? or are the ones i am having ok? i usually only have 3-4 a day.

just curious,

diane

gfbaker

I am an intermediate metabolizer and I have no hot flashes whatsoever. I would press to get the test done, because if you are an intermediate, you have to pay attention to the other meds you might be taking, and if it isn't working then you need another option. My onc rarely does them because most of his patients are menopausal and on AI's.I guess this is pretty common. My insurance covered the cost of the test.

Good luck!

lexislove

I tested as a POOR metabolizer. I have hotflashes.

I stopped Tamox for 3 weeks before my exchange surgery....hotflashes stopped. lol.

Im not convinced about this test.

Kashcraft

Here is the study about hot flashes and tamoxifen. There is a modest correlation, but note the study conclusion in bold.

http://www.ncbi.nlm.nih.gov/pubmed/19153830 

Women with reduced CYP2D6 activity have low endoxifen concentrations and likely worse long term benefits from tamoxifen. We investigated the association between CYP2D6 genotype and tamoxifen-induced hot flashes in a prospective cohort. We collected hot flash frequency and severity data over 12 months from 297 women initiating tamoxifen. We performed CYP2D6 genotyping using the AmpliChip CYP450 test and correlated inherited genetic polymorphisms in CYP2D6 and tamoxifen-induced hot flashes. Intermediate metabolizers had greater mean hot flash scores after 4 months of tamoxifen therapy (44.3) compared to poor metabolizers (20.6, P = 0.038) or extensive metabolizers (26.9, P = 0.011). At 4 months, we observed a trend toward fewer severe hot flashes in poor metabolizers compared to intermediate plus extensive metabolizers (P = 0.062). CYP2D6 activity may be a modest predictive factor for tamoxifen-induced hot flashes. The presence or absence of hot flashes should not be used to determine tamoxifen's efficacy.

bcincolorado

Thanks so much for the info about this test.  I will defiitely ask my onco when I go in to see if he has run the test.  I am getting awful hot flashes, but it sounds like it might nor might not be working like it should.  Better safe than sorry.

Pure

that is such crap-my oncologist told me the same thing. Umm how could that be if I am already having hot flashes from chemo? How are those different then the ones from Tamoxifin?

Mamita49

the only way to know is the test. Hot flashes says nothing about the gene mutation and if you can metabolize a drug. I have a friend who is tripple neg. and she has severe hot flashes.....

Get the test. 

oceangirl654

hopefor30, What does your oncologist want to do since you are an intermediate metabolizer? did you stay on tamoxifen or take toremifene instead? Thanks for letting me know!