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Daily Tamoxifen & Estradiol Lab Test

How will daily tamoxifen effect the ultra sensitive estradiol lab test. I’ve searched and read but I can’t find anything. My understanding is that while on tamoxifen there is still free E2 in the body. What I don’t know is exactly how the lab test works. Does the tamoxifen cancel our what would otherwise be shown? Any ideas or experiences?

Tamoxifen should have no effects on the levels of estrogen present in the body. That’s not how serms work.

Therefore there should be no effect on any type of estradiol test.


If the Nolva is signaling the balls to produce T, and as a consequence e2, could Nolva cause serum e2 to be higher?

Yes. All the studies shows nolva raises test, e2, shbg, and lowers igf-1.

From personal experience nolva did not raise my estrogen on a test. It also didn’t raise my testosterone. These were test done while I was using exogenous testosterone so maybe that has something to do with it.

Iv never gotten a test done during pct while taking nolva and not using exogenous testosterone.

I have ran a pct one time and it wasn’t pleasant and I didn’t recover well (altho it should be noted my testosterone leves before ever using aas were never great) which is why I blast and cruise now.

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That is wrong. SERMs throw off Estradiol blood tests. You cannot accurately test Estradiol while taking a SERM. I have also verified this myself by testing myself multiple times at labs within the same day even. It went from very low, below range and mid-range.

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However, the first point is both correct and incorrect depending on the dosage of Tamoxifen being used. It won’t normally affect the actual Estradiol level present in the body at normal doses. BUT, if high enough doses are used there is potential for an AI estradiol reduction effect because Tamoxifen converts to Norendoxifen which has been shown to have potent AI effects on par with Letrozole.

I’m just giving my personal experience.

And Fwiw the dose I was taking was 20mg/day

I took 20mg/day for 6 weeks and had labs done and my estrogen & testosterone levels while on TRT were almost identical to what they were before the Tamoxifen.

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Same I saw no difference

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So while taking test the stimulation effect of Nolva is probably very low to none. Wouldn’t be a good substitute for HCG either given that. I was curious about that

I was thinking about taking it when not on cycle or TRT. Idk what the labs would say in that case. Nolva has additional effect on the HPTA off cycle.