We are aware that there are bugs with our online community, and we still working through the bugs list and retrieving missing content. Thank you for your patience.
Side effects of Tamoxifen compared to Letrozole
I have just been put on Tamoxifen after Letrozole. My understanding is that Tamoxifen blocks oestrogen receptors on hormone-receptive breast cancer cells, whereas Letrozole helps prevent the actual production of oestrogen.
On Letrozole, I definitely had symptoms of low oestrogen. My question is, why do ladies experience menopausal symptoms on Tamoxifen if there is still oestrogen in their bodies? How else does Tamoxifen work, apart from blocking the sensors? Does anybody know?
I have only been on Tamoxifen for a week and it is too early to say whether I will have side effects. I can, however, tell that the Letrozole has stopped working because (to put this delicately) the area down below is not as dry.
Ann x
Before someone with a better brain replies: I gather that Tamoxifen, as you say, blocks the receptors by sort of docking onto them, but actually not 100% docking on, just enough to prevent oestrogen docking on. In the rest of the body, it has an effect more like oestrogen.
Hmm, that doesn't really answer your question, does it?
Margaret
Yes, that's what I read. Hence, the question. I suspect that something else is going on that is not fully understood. I shall be interested to see whether I get more or fewer symptoms. I would have thought the ones from Letrozole would have been far worse but time will tell.
Ann x
Ann
I've been on both. Tamoxifen for 6 months post surgery a year ago, then got a new primary last June and have been on Zoladex to suppress ovarian function (am pre-menopausal at 37) plus Letrozole since September.
After 3/4 months on Tamoxifen I was very dry as you described but nothing else much to note except light periods. On the new combination, not the same dryness problem but the joint aches and tiredness are pretty bad. But obviously all of this is anecdotal and very personal. All the drs assured me I would have hot flushes on my current medication but this hasn't happened. Goes to show they can't predict the impact. I am also now much more forgetful which is totally not like me.
C2010
Claire
My poor memory was the worst symptom when I was on Letrozole. The joint pains eased after a while. Letrozole cased the dryness but, so far, Tamoxifen is having the opposite effect, which I hope will lessen.
Good luck, anyway.
Ann x
Thanks Claire & Ann for confirming that you both suffer from memory issues on Letrozole. I spoke with my Breast Care nurse about my memory issues and she said she had not heard of anyone having memory problems whilst on Letrozole, she said its probably stress related. I can now relax a bit knowing that I am not the only one with this problem,
Morning all - just having a read of this thread. I am on letrezole and have very sore patches around my eyes, inner and outer corners, anybody else got this? And if so, any suggestions? My GP suggested E45 or aqueous cream - seems to be the answer to everything!
I also have the memory and forgetfulness problem, so was glad to read that others have it too.
Best wishes
Katieb
Hello Katieb
Haven't heard of sores around eyes but I have sores just inside mouth on bottom lip. Been on Letrozole 3 years and have had problems with mouth 6 months after starting on it, been diagnosed with Burning Mouth Syndrome.
I'm finding that if your SE isn't a common one then my Onc will say that it isn't the drug causing it.
One thing I thought of, is how do the drug companies know when patients are having problems with the drug,do they get feedback from Oncs re SEs?
Hope it clears up soon.
Hazel
Hi Hazel - thanks for your reply.
Sores in the mouth sounds nasty - had lots of problems with mouth during chemo.
You would hope that drs give feedback to the drug companies. I did a trial for letrezole for 2 weeks before my mastectomy but didn't have any side effects then but don't think I was on it long enough. They were trying to see if it would shrink the tumour - never got any feedback on that either!
Katieb
Hi everyone, I have not been on the forums for some time, but my visit to the ONC yesterday has worried me a litle. I was put on the trial for Letrozole before my op which was last November, which was fine, then it was continued immediately after my operation and I have been on it ever since. I did not think I was having any side effects until I realised that the pain in my right arm that I had put down to arthritic shoulder, was now between the shoulder and the elbow and at some times quite painful making it difficult to reach up at all - so I mentioned it to the ONC and she found the spot alright, I nearly lept off the bed!! Sent me for an xray and will come back to me if it shows anything, but also said that I should stop the Letrozole for 6 weeks and that she may change it when I return to the tablets. Reading all this on here I wonder if I will be put on Tamoxifen and some of the SEs on here do not sound nice at all. Inflammation of a muscle is suggested, and I now feel that perhaps that is better than some of the SEs you all are having. Anyone on here gone from Letrozole to Tamoxifen and can tell me how they got on?? I have very dry lips as well, but that is all, no soreness, wondering if Letrozole may be the best of two evils!!
This may be my naviety, however I thought that Tamoxifen was prescribed if pre menopausal and Letrozole if post menopausal. Tamoxifen reducing the oestregen production from ovaries and Letrozole shutting down oestregen from joints, hence the joint pain and increased risk of oesteoporosis (prob spelt wrong!) on Letrozole. What is others understanding? J.
jaynek, no, see what Ann wrote in the opening message: TAM docks onto oestrogen receptors, AIs prevent oestrogen production: they both do the job. You can only have AIs after menopause (roughly speaking), but you can have TAM before or after. TAM is a bit weird in that it has an oestrogen-like effect in the body, whereas AIs can make osteoporosis worse.
I've gone back from Arimidex, which is similar to Letrozole, because I didn't like the side effects. There are some serious side effects with TAM, but they're OK in my case (I'm not at special risk for thrombosis, my eye check-ups have revealed no deterioration, I have regular gynaecological exams to catch thickening of the uterus lining).
One question is: are AIs more effective than TAM? If so, not very much. So much money has gone into advertising them while they were not generic that I think a lot of people think they are much much more effective than TAM.
My Onc said this week: slightly more cases of recurrence with TAM than AIs, but number of deaths and time of survival rates are the same (this is cheerful stuff, isn't it?). He said the reason why just as many people die on AIs is probably because they raise cholesterol and stop people taking exercise because of bone pains, i.e. more heart disease results.
Margaret
Hi Margaret
Thanks for that - that makes sense. I am experiencing side effects of the Letrazole, some I am coping with much better than others. The vaginal atrophy is one which is being discussed on another thread. Certainly not something I was ever advised about which I think is quite a significant failing. Anyway, as I say, on another thread! Take care all. J.