I have completed 8/20 sessions. The procedure itself is not too bad and the staff are wonderful. However, I have hit a problem. For the first two days after treatment started I was unable to pee and was in such pain that I had to go to A&E who fitted a catheter which gave me much needed relief. The radiotherapy staff can continue with treatment which is a relief. Is this a known side effect or was it just an unlucky coincidence?
Hello Rawsoftba9a24
I wasn't sure so I checked my resource bank and it's one of the rarer side effects.
The radiotherapy can cause the prostate to swell and it can also lead to inflammation of your bladder and urethra and stop you emptying your bladder.
As an aside my prostate grew without any radiation and stopped me peeing (click on my avatar for my journey) and I ended up with a catheter for 10 months - so if you need any help in that department just drop me a message.
Best of luck with your final 12 fractions - keep us posted as to how you get on.
Best wishes- Brian.

Macmillan Support Line - 0808 808 00 00, 7 days a week between 8am-8pm
Strength, Courage, Faith, Hope, Defiance, VICTORY.
I am a Macmillan volunteer.
Thanks, Brian. The catheter is giving me some relief and, sadly, I will keep it in place until I have finished the radiotherapy. One thing at a time. Thank you for your words of encouragement. Just my luck to get one of the rarer side effects.
As Brian said it is unusual.
I can tell you that I had more difficulty peeing when I was on radiotherapy in the middle 2 weeks, but it never actually stopped.
It gradually resolved over a period of a couple of weeks and is now ok.
So, hopefully, you will get your rhythm back once the side effects of the radiotherapy fade. The cancer cells are, of course, having a significantly less good time,
Steve
Changed, but not diminished.
Hi Rawsoftba9a24 (893ce8f56e0f4740bd29976649c35864) I had a similar experience to yours when I was at 4/20 RT sessions. I had issues getting comfortable with the catheter, but the 2-litre night bags make a decent night's sleep a possibility.
One thing I was told by the cancer hospital; don't do pelvic floor exercises with a catheter in place. I'm unsure what would happen but it took it at face value.
I'm wishing you the best with your treatment.
Chris
Thanks for the helpful comments. I have been continuing with my daily exercises but, in view of what you say, I will omit the pelvic floor exercises. I do not want to do anything to prejudice the radiotherapy. Thanks again.
I appreciate the supportive comments. I am hanging my hat on getting back to some sort of normality when the radiotherapy is done. Thanks again.
Hi
This did happen to my husband but just after radiotherapy finished not during. He suddenly was unable to pee which meant a visit to A and E and a catheter fitted. This was removed by urology two weeks later and all had returned to normal. This happened almost two years ago and he has had no further problems with this
Whatever cancer throws your way, we’re right there with you.
We’re here to provide physical, financial and emotional support.
© Macmillan Cancer Support 2026 © Macmillan Cancer Support, registered charity in England and Wales (261017), Scotland (SC039907) and the Isle of Man (604). Also operating in Northern Ireland. A company limited by guarantee, registered in England and Wales company number 2400969. Isle of Man company number 4694F. Registered office: 3rd Floor, Bronze Building, The Forge, 105 Sumner Street, London, SE1 9HZ. VAT no: 668265007