Changing from Tamoxifen to Anastrozole

Hello, After three and a half years I’m about to switch from Tamoxifen to Anastrozole (am 53 and tests show I’m post menopausal) and was wondering what that might mean in terms of everyday life. Are the side effects better/worse? I’ve been taking Tamoxifen in the evening - should I do the same with Anastrozole? Really want to avoid having hot flushes at work, etc. Would be very grateful for any advice and to hear about your experiences.





While you are wating for some other members to come along with some replies for you, I’ve attached a link to our publication on Anastrozole which I thought might help:

Very best wishes


BCC Moderator

My personal experience is that I took Tamoxifen for 2 and a half years and asked to change due to problems with cystitis and weight gain. I had heard there were a different set of side affects with Anastrazole but wanted to give things a go.

For the first few months there was no change and in fact I managed to lose a few pounds in weight, but in January this year had a ‘muscular’ attack that was so dramatic I ended up in the urgent care centre at the local hospital!

From this time, unfortunately, I must say that I have not had a good experience with this drug, with pain in my wrists and thumbs, no grip, fatigue, general joint pain and on particularly bad times, having to stay in bed in the mornings for an extra hour with a complete lack of energy.

I wanted to persevere as I understood the drug had good results with regards to breast cancers but after a year I have today seen my consultant and been prescribed Tamoxifen again.

The consultant said I should have gone back before with such severe side effects which also include raised blood pressure and cholesterol  - so more medication - so I think I will have to be grateful for the ‘lesser’ side effects of Tamoxifen that may come with changing back again…

However, I was reading that some women take Anastrazole for five years with relatively no side effects - so I am just unlucky I guess - but you can’t say I didn’t try ?


I hope your changeover has been better than my experience and we all need to weigh up the pro’s and cons

Good luck with everything xx