Does Tamoxifen Counteract Exemestane (Aromasin)



Hi Everyone – I am new to the forum, and I am very thankful to have been invited! I heard elsewhere that Tamoxifen counteracts Exemestane (Aromasin). Does anyone know whether or not this is true? I’ve read all the related posts I could find, but I did not find that specific answer.

Based on my bloodwork (listed below), I am also hoping for some guidance on the dose of Exemestane I should take and (based on half life) if / when I should stop taking Tamoxifen before I start taking Exemestane.

I am currently taking 10 mg Tamoxifen twice daily (for the past six weeks) to successfully counteract tender, sore and lactating nipples. I just ordered Exemestane (Aromasin) from United. I hope this will counteract the constant bloating and massive water weight gain I experience, even on a clean diet. If it helps, I find the bloating and water retention increases with carbs.

I have no sex drive, and I also find it incredibly difficult to find any motivation to train. I go to the gym out of habit, only to find I can’t get motivated once I get there. At best I do a few exercises. At worst I go home. I’ve been going home more and more lately, which is incredibly frustrating.

I am 52 years old. I am almost 6 feet tall, and I weighed 205.4 pounds this morning. I started a prescribed TRT dosage of .5 mL / week on March 9th. After an initial round of bloodwork, my doctor increased the dosage to .7mL / week in early April. My doctor refuses to prescribe anything for high estrogen or prolactin levels. He is the second Endocrinologist I’ve worked with, and I feel I had to twist his arm to get him to prescribe testosterone for me in the first place. The first Endocrinologist said he thinks TRT will be the next “Opioid epidemic”, and he promised he would never prescribe testosterone for me, even if I have a tumor on my Pituitary gland. I paid almost $400 to hear that!

Here is the bloodwork information:

2/5 (before TRT)
Prolactin 15.5 ng/mL (Standard Range 4.0 – 15.2 ng/mL)
Estrone 42 pg/mL (Standard Range 12 – 72 pg/mL)

2/26 (before TRT)
Macro prolactin:
Prolactin Serum (ICMA) 7.7 ng/mL (SR 3.0 – 18.0 ng/mL)
Monomeric Prolactin (ICMA) 7.5 ng/mL (SR 3.0 – 18.0 ng/mL)
Percent Macro prolactin 3% (SR 0 – 49%)

Sex Hormone Binding Globulin 31.7 nmol/L (SR 19.3 – 76.4 nmol/L)
Estradiol 17 Beta 6.5 pg/mL (SR 12.6 – 44.0 pg/mL)
Testosterone 112 ng/dL (Standard Range 280 – 800 ng/dL)
Testosterone Free 6.8 pg/mL (Standard Range 7.2 – 24.0 pg/mL)

3/31 (TRT started 3/9)
Prolactin 30.2 ng/ML (Standard Range 4.0 – 15.2 ng/mL)
Estradiol 17 BETA 11.5 pg/ML (Standard Range 12.6 – 44.0 pg/mL)
Testosterone 393 ng/dL (Standard Range 280 – 800 ng/dL)
Testosterone Free 15.4 pg/Ml (Standard Range 7.2 – 24.0 pg/mL)
Hematocrit 48.2% (Standard Range 39.0 – 51.0%)

I will get additional labs done in a few weeks for Testosterone total, macro prolactin, hematocrit and Estradiol 17 Beta.

I appreciate the time you have taken to read this. Thank you in advance for your help!


First off welcome and we are happy to have you part of the community.

You have to find your balance when it comes to TRT. Your estrogen is low which would coincide with your symptoms of no energy and low sense of well being. Combining tamoxifen with aromasin with a 140mg/week of testosterone (I am assuming your prescribed testosterone is 200mg/ml) is asking for trouble. So I am glad to hear that you are not considering using them both. The half life of tamoxifen is roughly 7 days. I am not going to make a recommendation on how to transition because I think there is something else going on with your health based on the post.

If you are experiencing the symptoms with lactating nipples, bloating and massive water weight gain on a very small dose of testosterone you need to NOT try and self prescribe. I would highly recommend you continue with professional medical help and follow their recommendations. In the mean time you can search out a naturopath doctor (ND) in your area the specializes in male hormone replacement therapy.

Be very cautious about messing with your hormones without experience by taking advice given over the internet.

Good luck and I sincerely hope you find the help you need to be the best that you can be.


Follow up… I am 50+ and have been on TRT for over 5 years. The process of finding a medical professional who actually knew what they were doing took me almost 2 years. MD, Endo’s and TRT clinics I discovered were pretty much useless. I was blessed to find a ND in my area that specialized in hormone balance. Not only TRT but EVERY hormone. Once my hormone levels were in balance, which took about 4-6 months, my life changed for the better.

There are professionals out there who really want to help but I discovered I had to take charge of my health and look real hard to find one because I deserved it! :wink:

You might want to consider donating blood. Your hematocrit is getting in the upper range and with the water retention I am guessing your blood pressure is elevated.


How’s everything brother welcome to UGM I was reading but I’m actually driving at the moment and I started to see some things that worried me. If you could brother shoot me private message. I saw some things about your nipples lactating and I’d like to help you out just at the moment I’m on able to because I’m driving I’m actually using speech to text right now so if you could hit me up I’d like to talk to you and help you get things figured out.


Thank you for taking the time to help! I actually plan on donating blood in two days :grin:

Based on your feedback, my wife is looking for an ND in our area.

As for my estrogen levels, I wonder if they are high for me - especially since they almost doubled 15 days after I started TRT.


Hi Bigmurph - I sent you a PM. Thank you so much for taking time to help me get things figured out.