RT and Testosterone

Email this conversation Print this conversation

User

Posted 09 Dec 2025 at 22:32

Originally was discovered with a PSA of 69 before treatment began culminating in a RP!

So now 2.5 years since my RP, PSA slowing creeped up hitting 0.19 and resulting PET CT scan 3 months ago showed nothing yet, but it's there somewhere. I'm now on Bicalutamide for 2 years and having RT to the prostate bed and lymph nodes starting next week for a month.

So nearly 3 months in taking Bicalutamide 150mg and Tamoxifen, and my testosterone has hit 73.35 3 times what it should be. Is this normal? Nobody warned me about this.

I will be starting RT next week, would anyone have any advice to make this particular part of the journey a bit easier. So far the hormone treatment has been fine as regards side effects maybe feeling extra tired. Any words of wisdom would be greatly appreciated.

User

Posted 10 Dec 2025 at 08:38

Hi Gerry,

I know Bicalutamide blocks the effects of testosterone, rather than stop its production like zoladex/prostap.

So does it accumulate as its not being used up (if that's a thing) or does Bicalutamide increase its production? I'm not sure.

As to RT, it was my primary treatment along with Brachytherapy. I found the RT very manageable and worked through-out. There was some increase in urgency for the toilet but never felt in fear of not making it, wet farts were also a thing which increase more after the RT finish and carried of for a couple of months. I would say a year on I'm back to 99% normal. I avoided caffeine and alcohol and spicy food during treatment too.

I'm on hormone treatment for 2 years (zoladex) and have the normal side effects, weight gain, muscle loss, loss of libido, hot flushes (though very mild). It's been manageable but I'll be glad to be off it (7 months to go!)

My advice would be try and stay active, walking, resistance training using weights etc.

I'm sure the side effects leave quicker with Bicalutamide rather than zoladex/prostap injections so that's a good thing for you. though I think Gynecomastia (breast tissue growth) is more likely. You can be prescribed Tamoxifen to stop this.

I don't know where you are with ED after your surgery, but that's also a thing with the hormone therapy. I was prescribed a vacuum device and tadalafil (which I topped up with my own purchase) to try and avoid atrophy. Hopefully will return back to some normal after HT

All the best

John

User

Posted 12 Dec 2025 at 18:31

Thanks John. From a quick Google this is what I found courtesy of AI.

Yes, bicalutamide actually increases testosterone levels in the body, even though it blocks testosterone's effects on tissues, leading to a paradoxical rise in blood testosterone and estrogen due to feedback loops, which is why it's sometimes used with other drugs or in transgender care for feminization, notes ScienceDirect.com.

How it works:

Androgen Receptor Blocker: Bicalutamide's primary job is to bind to androgen receptors, preventing testosterone (T) and dihydrotestosterone (DHT) from acting on cells, particularly prostate cancer cells.

Feedback Loop: When the body senses that testosterone isn't working (because the receptors are blocked), the pituitary gland releases more Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH) to try and stimulate the testes to produce more testosterone.

Increased Production: This increased LH signals the testes to pump out more testosterone and estrogen, causing blood levels of both hormones to rise, sometimes significantly (up to 80% or more).

The problem is my testoterone has increased by 300%. When I spoke to the nurse she came back and said after speaking with a specialist this was okay! I'm not convinced and it would be good to hear from someone else if this is indeed the case.

Email this conversation Print this conversation

Join the online community now.

Click through to become a member and gain access to support, information and real time replies.