Womb cramps with tamoxifen woes

I have been on tamoxifen for nearly two weeks now. Yesterday horrible sharp womb cramps started, not sure if it’s the tamoxifen? Has anyone else experienced this. I had a mirena coil in before BC but had that whipped out sharpish. The oncologist has said I am post menopausal and haven’t had a period in the last two months since mirena was removed. 


I am 50 and before BC was jogging nicely with my HRT patch ( in hindsight probably a big mistake) I was fine and juicy. Now I feel such an old woman, an achy hip which I was really worried about bone mets, had an MRI and its bursitis. I am having such bad sweats through the night I can’t sleep. I am so tired during the day probably due to poor nights sleep but also oncologist said tamoxifen can cause tiredness. 


I am am due to start radiotherapy in a couple of weeks and I know that can make you tired too !


My brain is not functioning as it did. I can’t multitask anymore, is this the lack of sleep, tamoxifen or just the huge thing that BC is? 


I had a WLE SNB - IDC 14mm grade 3 oncotype 20 no chemo. I wonder will I ever feel alright again? 

Hi Kimucoughdrop, 

I am really sorry to hear you are experiencing these cramps. I am sure some users will be along to offer support and share. You may also want to take a look at our page on Tamoxifen.

In the meantime please do call ourhelplineat 0808 800 6000 who will be able to talk to you about what you have been experiencing on tamoxifen, answer any questions you might have and offer a friendly ear. The opening hours are below. 

Monday-Friday, 9am-5pm
Late opening Wednesday 9am-7pm,
Saturday, 9am-1pm

Best wishes, 


Hi Kim


I’m on my second go at Tamoxifen as I had the same pains as you. Been back on them for just over 6 weeks and the pains are back. Didn’t have them before I started taking Tamoxifen and they did ease off then go away during my time off them. Really struggling to know what to do next, want to see if I can ride it out and see if it settles after a few months, but when it’s bad it’s very debilitating and tiring. Soluable paracetomal eases it slightly but doesn’t take the pains away.

Sorry my post isn’t very positive, but just wanted you to know that you’re not alone, as when it first happened to me I couldn’t find any info on it happening to anyone else and it was frightening, so thought it was important that you knew it can happen. It is a rare side affect my oncologist said but can happen.

As for the tiredness you are still at an early stage and it took me a long time after my surgery and radiotherapy, before I stopped feeling tired and getting ‘brainfog’! I still can get very tired if I’ve overdone it, give yourself as much time as you need to recover. You will feel better eventually, I did, it just takes longer than we would like sometimes. Good luck with the radiotherapy :smileywink:


Take care


Julie x 

Hi Kim

I’ve been on tam for nearly 3 years and I get tired too. I think your stomach cramps are unlikely to be the tamoxifen so soon It took me a long while to experience any “side effects” as it builds up in your system. Im 51 and still pre menopausal My Breast surgeon always says Tamoxifen might mimick menopause but it doesn’t bring it on. Do you mind me asking did you receive an onco type dx test free on NHS? I do think we are changed for good but there’s lots we can do to make us feel better.(tai chi,mindfullness, yoga, fresh air! whatever!) I hope you find your thing.  Be kind to yourself! Take a nap if you need it. Keep a notebook or journal 'been proven that writing down our concerns or worries or just ranting on paper is very beneficial. you dont have to keep your writing but in my own experience, looking back at stuff i wrote down 2 years ago, it’s amazing how far we come! :smileyhappy: Definitely see someone about your cramps though. good luck with rads I went in everyday, smiled and asked everyone how they were. Music helped in the room if they dont have any maybe ask? :heart:

I have been in TAmoxifen for about a year. Period stopped 6 months ago. The last two months I have been having PMS symptoms, bloating, cramping on both sides and lower back pain… has been goin on and off for about a week. Going to get a transvaginal ultra sound tomorrow… it’s very uncomfortable!.. take each day as it comes… good luck