can we check how effective tamoxifen is for us?

Just wondering if anyone knows if there is any way to check if tamoxifen is working or not? I’m concerned cos I hardly have any hot flushes and just want to be sure, if I can, that this is the right treatment cos a hormone test showed I’m postmenopause but cos of my age it was decided tamoxifen for 1st 2 yrs then change!Any advice or info would be very welcome.

Hi Smiler,

Can’t answer your question I’m afraid but wanted to post as I too am curious as to how they know if its working and if they check.

I have only been on tamoxifen since 10th March and so far haven’t had anything I could contribute to a side effect - in fact the horrid nightsweats I had been having since surgery in September have stopped!

I am 40 and was 39 at dx so guessing I was/am pre-menopausal but there again - does anyone test?

Was told by my Onc that they wouldn’t test me during the 5 years to see if I had gone through the menopause and thereby switch me to something else, another thing I found odd.

really good post! Thank you for bringing this up. I’ve been on T since sept (age 38 at diagnosis) and have had no flushes which I am very grateful for but as still having (horrific) periods was worried why my onc didn’t give me Zoladex as I know lots of women are on. My onc has given me a reason why he doesn’t prescribe it and I am happy with that and especially hearing the side effects here I am pleased not to have it but deep down I do wonder if I’m more at risk of recurrence still having such active ovaries and all the hormones associated with it.
I agree with your question, how do they know if it’s being effective? I’m also Her 2+ and read somewhere that this can make you become Tamoxifen resistant. Has anyone else heard of this or did I just dream it?
E xx

E, My periods continued throughout chemo (though ended up being every 6 weeks and heavy), not had a period since last chemo (10th Feb) but have had period pains for the last few days and not sure whether they will return now that I am on the tamoxifen.

Might be too soon for the drug to have hit a level in my body to stop them (and cause side effects) as it takes a couple of weeks to get to a level in your blood stream but have to say I would be worried 6 months on tamoxifen to still be getting periods as presumably as you say your ovaries etc are still doing their stuff.

Don’t know about herceptin and tamoxifen resistance but did read an american article the other day about the fact that tamoxifen can stop working because the cancer cells get a resistance.

Hi Smiler

Really good question. I dont have menopausal side effects with the drug either and have been taking it since last August. Just the weight gain! I was premenopausal prior to commencing treatment.

I read somewhere on here that the percentage increase life expectancy of taking it was tiny for some women. Has left me feeling that I need to know what the drug is doing for me and what my percentages are. Think I will bring this up at the Onco in 3 weeks.

Best wishes Judy

I would also like to know if Tamoxifen is being effective.I have had no hot flushes so feel lucky about that but I am suffering fatigue which is making my return to work difficult.The more I read the more I want to contribute the fatigue to my Tamoxifen!
The Drs seem to think I should count myself lucky to have no hot flushes!
I have a mirena coil (which I have been assured I can keep) so I have no periods as a guide.
I have read some patients get Zoladex,does that do something diferent to Tamoxifen? I believe it has side effects too!

I am just going through the process of uncertainity re tamoxifen.Became menopausal on chemo. Recently read in nice guidelines that letrasyl and zolodex maybe more effective but research show that the letrasyl may not be so effective at suppressing oestrogen if not fully menopausal so will have blood tests to clarify that then discussion with oncologist

I’ve been on tamoxifen for a year. My periods have been very patchy since chemo (46, finished chemo a year ago). I don’t think the tamoxifen interferes with your own hormones, but blocks the receptor on the surface of the cancer cells which would be triggered to grow by oestrogen in your bloodstream. They can’t do a hormone blood test while you’re on it because the tam would affect the results of the test. So, for all us ladies who aren’t quite sure if we’re fully post-menopausal yet, tamoxifen is the best thing to be on, until there is absolutely no doubt.
I’m almost certain this is right - someone correct me if not!


I also am concerned as I have been on ‘relatively symptom free’ Tamoxifen since July 2007, no hot flushes or weight gain.
However one question I would like to add to this thread, has anybody else had ovarian pain and ‘growths’? My periods never returned after chemo 2 years ago. (I am 43 now)but I was getting period like pains then my abdomen felt quite tender, I was referred to a gynaeocologist who sent me for tests, only to find that I had what he described as ‘tumours’ on my ovaries, fortunately blood tests indicate that they are benign. I am waiting surgery to have them removed, but it has already been postponed once. The gynaeocologist seemed to think that this is a side effect of Tamoxifen, but I haven’t heard any mention of it on here.

Don’t want to panic anyone, because I’m not worried about them, but would just rather get on with life rather than be back in hospital and have more time off recovering. But has anybody else heard of this?

Take care


It’s reassuring to know a lot of us have similar questions and worries and it’s not just me worrying too much! I haven’t had a period since my first chemo, but no period type pains either. Let’s just hope tamoxifen is doing it’s stuff for all of us!

I,ve been on tamoxifen for 3 years now, had night sweats, put on a stone in weight and have had to have ovaries removed because of cysts which doc said this was a side effect of tamoxifen, now having terrible night sweats as gone through menopause,

lorna xxx

Very interesting post. I have been on Tamoxafin for 8 months, had a few side effects at first but none now, was told I must have mirena coil removed so now have regular heavy periods. (so is it working as I thought periods would stop)


Don’t think I’m as lucky as some of you, I have full on side effects…not hot but ‘sub- tropical’ flushes and sweats at night that can only be likened to near flooding! May soon have to resort to plastic sheets; and there’s me thinking they wouldn’t be needed for at least another 60 years, when I will be fashioning a pair of plastic incontinence knickers to match!. Putting on weight is not a problem so long as I stick to ½ can of diet coke and 1 ryvita (no filling) a day! Tamoxifen a delightful pharmaceutical concoction! ‘Want to walk around all day with a red face?’…no problem, ask your pharmacist for Tamoxifen! Why can’t scientists discover drugs with side effects such as ‘Beware may slim and tone body, decrease winkles and frown lines and has been know to make some women an irresistible magnet to men’…hayho.

Anyway, after chemo and no periods I’m unsure if I’ve crossed the line of no return and become ‘post’-menopausal. The doctor has suggested to me I wait for another year or so and if my periods don’t return then I come off the tablets (that’s if I haven’t combusted from overheating in the meantime) and they will check my hormone levels with a view to maybe moving over to AI’s. I’m hoping that’ll be the case so worries of Tamoxifen resistance will be alleviated.

Interesting what you have said Nickie about ‘period pains’. Do you remember how long you had been on Tamoxifen when the pains started? I’ve been taking it for 6 months now and have just started having ‘period pains’, which I haven’t had since I was a teenager…if only my wrinkly skin would revert to those days!

Just scanning through your posts…

Mirena coils can cause cysts on ovaries…I had to have mine out last week.

Zolodex stops your ovaries working temporarily. It is an injection which you have either 1 or 3 monthly. It is like a less effective oopherectomy. I am having an ooph and will still remain on tamoxifen for a few months following the op before switching to arimidex.

Apparently a year of arimidex during the course of your hormone treatment has proved to be beneficial for those post menopausal.

Also a blood test can tell if you are pre/peri/post menopausal but you still wont be considered suitable for arimidex until you have been period-free for at least 12 months.

Hope this helps…I am sure we all get slightly different information but I am basing this upon what my bc onc and gynae onc has told me

I’m 39 and last had a period in June 08 just after my 1st chemo. Been on Tam since middle of Oct 08 and hate the side effects. The red face is a constant visible sign to me, and makes me look much healthier than I feel which I suppose is a double-edged sword. The hot flushes are not just at night now, I get them in the day too, often at very inconvenient times at work.

I have dry eyes (except when I’m crying, which I have extremely uncharacteristically been doing a lot of lately) and itchy backs of my hands. The hands are worst during a hot flush, but there is absolutely nothing to see.

I have awful cramps in my legs at night time, which last for ages and of course keep me awake - as if the hot flushes didn’t do that enough.

I mentioned all this to my surgeon when I saw him this week, and his very firm advice was to keep on with the Tam, as it has a cumulative effect with the chemo - so if the chemo increased your chances by 20% and the Tam alone by 4%, the overall cumulative effect could be as much as 35%, which at my age and with children aged 5 and 3 is worth it.

It seems to vary as to whether they test you to see if you are post-menopausal and can go on to AIs. Does anyone know if the hot flushes stop when your menopause finishes?

Hugs to all


I’m similar to you. I’ve been on Tam for a year. Dx at aged 40. The side effects got better on Tamoxfen rather than the chemo. Now I just have day-time hot flushes, which I swear got worse after drinking cranberry juice. I will experiment again!

I did have a blood test to see if I was pre or post menopausal. I was still pre but that was almost a year ago. I haven’t had a period since after the first chemo session in Oct 07. I will raise the question at my next check-up Friday.

all the best - Wizz

Hi all, I am a new poster on this new website, I posted on the old one last year.
I was diagnosed with BC in October, had 10mm grade 1 removed end of November and 2 nodes which were clear, 3 weeks of radiotherapy in January and have been on Tamoxifen since beginning of December. Had the hot flushes but have been quite lucky until I came on here to get answers as to why I have this lower abdominal pain. It would appear this is quite common from the posts on here. I rub my hand across the skin and there is like a line of little lumps where Im getting the pain and wondered if anyone has had this aswell. It has freaked me out a little bit and don’t know whether I should get some advice. I have also had normal periods from day one of Tamoxifen.


Hi Sandra,

I’m in a similar position to you, I was diagnosed at the beginning of November with a 13mm lump, stage one, grade 3 which was removed in November and then I had some more tissue removed in December, I started Tamoxifen in January and then stopped taking it while I had radiotherapy, started the Tamoxifen again mid-February and have experienced period like pains since. I’ve got an appointment on Tuesday with the oncologist and I’m going to mention it then. I think its probably all connected with hormones and all those related bits and bobs but I feel that once a cancer diagnosis has been made I have become quite paranoid about every ache and pain that I have.


sorry to jump in here,just noticed that you said you stopped taking tamoxifen during rads… I have just started taking tamoxifen(yesterday) EEEEEEKKKK am waiting to get rads appointment thro in next couple of weeks but havnt been told that will have to stop it.Just waiting for the hot flushes to start…

Hi Sandra44,

I had my radiotherapy at Christies in Manchester and it was there that I was advised to stop the tamoxifen for the duration of the radiotherapy but a friend of mine who was under the same consultant as me at our local hospital but under a different consultant at Christies wasn’t given the same advice. I asked the BCN about this who confirmed that women were being given different advice from different doctors. The reason given for not taking the tamoxifen was that it makes the cells ‘sleepy’ and in order to zap them the radiographers need them ‘up and lively’ it made sense to me at the time and I was quite happy to stop taking it but have found that since starting to take it again I am experiencing more side effects than before.
Hope you don’t mind me passing on abit of advice before you start your rads, I was adviced by my BCN to use E45 cream before starting treatment to hydrate the area, advice that I followed twice a day before treatment and 4 times a day during treatment, I had 15 days of treatment and whether I was lucky or whether it was because of the advice but I had very little soreness, she also advised me to go ‘topless’ whenever I could to get the air at the affected area and I did find that very soothing. Hope all goes well for you.
Best wishes Olwen