antidepressants + tamoxifen

Hi Gocat

How are you going to manage the change from one anti-depressant to another ? Is there a weaning off period?

Let me know how it goes. I am thinking of going to GP with the article.( have to go soon for sick note etc anyway) Spoke to a different onc today but he had no idea about any of it !!

I think I would feel happier on Effexor as every article names it as lowest risk.

Anna x

hi Anna - what are you on? I was on prozac and my GP prescribed it in liquid form, a 5ml spoonful was 20mg so the same as 1 tablet, I reduced it to 4ml for a week or so the kept reducing it until I was on about 1-1.5ml where basically they said there would be no therapeutic effect. I then had 2 wks without and hoped to manage with no medication but found it wasn’t the right time - I was still in the middle of rads and got really anxious and twitched so started on efexor xl (this one is a slow release one which has less s/e’s apparently - pity it sounds like an extra large dose!!) Within a week to 10 days I started to feel a lot better…take care, mary x

ps apparently in the States tamoxifen comes up in prescribing with a warning for use with anti-depressants but not yet in the UK although a lot more Dr’s are aware of potential problems…

Thanks for your comments. I am on citalopram which is listed in some research as having little effect on Tamox and in others as having a moderate effect ( but not as pronounced as Prozac).

I mentioned it to GP a while ago and she said she would be happy to swap me to Effexor if oncs etc recommended it. Mentioned it to one onc and he said Prozac was a definite no-no but he wasn’t sure about citalopram. He went to look it up and came back saying it was ok. I then saw a different onc at my rads planning. He had no idea about anti depressants affecting Tamoxifen at all !!

I think my best bet would be to print off some of the articles and go back to GP !

When I went to the doctor on wednesday she had not a clue about bc. She actually wanted to change my antidepressant to prozac !! I know this is a no no with tamoxifen. I am having alot of problems finding an antidepressant to suit me as have tried so many in the past.


I am on amytriptylene and have never been told that they affect the Tamoxifen, now I am beginning to wonder.
Libby x

Hi Annalou, My GP just said to stop the prozac and start on the effexor. So far so good.

Good luck with your GP

Hi gocat

Have seen GP today. He was very honest and said I probably know more about this issue than he or onc do. He reckoned there probably wouldn’t be that much difference between citalopram and Effexor, but was happy to swap me if it was something I wanted to do.He put me on 75mg Effexor, which is the second lowest dose. Is that what you’re on?
I got the prescription for the Effexor and took it to the chemist, only to find that they had run out of it!!!

Will try Boots large branch tomorrow…

Hope you are doing ok ?

Anna x

Hi Anna, glad your GP listened to you. Yes, Im on 75mg daily too. Havent noticed anything different yet but feel reassured that my medication is not stopping the tamo doing it’s best.

Boots large branch didn’t have it either !!
Finally got it at a backstreet Lloyds! I think there is a problem with the manufacturer or something.

Also got my next Tamoxifen which is Wockhardt brand not APS, so hoping it doesn’t have worse side effects…

Anna x

Anna, mine is Wockhardt

Hi Ladies,

Can I join this club? I’ve been struggling with Tamoxifen side effects for the better part of this year. I finally had an assessment with a psych. yesterday & have been given a prescription for Citalopram.

I’m totally new to even the notion of taking antidepressants, so feeling a bit unsure, though I was pretty impressed by the explanation I was given about how they work. Anyway, I can see some of you have some experience with Citalopram, so any info would be appreciated……How long it took for the benefits to kick in, any side effects, how long it takes to come off again, that sort of thing. I’ll be doing a 10mg dose to start, going up to 20mg for 6 months.

Many thanks & all the best to everyone!


Hi Anna, my first months supply of tamo was APS and 2nd months supply is Wockhardt and there have been no extra side effects. Hope it’s the same for you.

Hi Linda, welcome to the thread. Havent got any advise re citalopram but wondered if you knew there is a tamoxifen thread at

Hi Gocat,

Thanks! I’ve been following that one too. Just never posted on it as my solution has been to give myself breaks from the stuff so I could function! (don’t tell anyone!:slight_smile:

Hi Linda

my GP put me on citalopram shortly after I was diagnosed. It took about 2 and a half weeks before I noticed any beneficial effects, and I haven’t had any side effects from it at all. It worked in lessening my anxiety and lifting my mood.I was also waking up with anxiety attacks and it stopped that from happening, thank goodness.

After reading about anti-depressants and Tamoxifen, I decided that it would be best if I could change to venlafaxine ( Effexor), as in all the studies that is the one that comes out as having the least interference with Tamoxifen doing its job.My GP was happy to do this and said I could make a straight swap.

In some of the studies citalopram was listed as being ok with Tamoxifen and in others it was described as having a mild inhibiting effect, so I thought it best to change as I have nothing to lose and possibly something important to gain.

I was on on 20mg citalopram per day.I think 10mg is the lowest dose. I was told you need to take it for anout 8 weeks before they decide if the dose is right for you. You then need to be on it for 6 months or more and have to wean it down gradually rather than just stopping.

Hope that helps a bit???!
Good luck, let us know how you get on

Anna xx

Hi Annalou,

Thanks for your post, it has helped!
Sounds like Citalopram worked well for you…

I had read differing reports about the best SSRI/Tamoxifen combo too, & I was trying to work out why my doc would go for the Citalopram over Effexor (thought it might be a cost issue), but I’ve just read that Citalopram works on serotonin receptors only, while Effexor works with other neurotransmitters as well. (Learning a lot about all this quite quickly LOL!)

The doc seemed to think my problems are strictly related to low serotonin uptake, so I guess that’s why he’s chosen that one. Some of my symptoms actually started before the Tamoxifen, so I’m starting to wonder if my chemo has played a role in all this too….

Interesting that you were able to swap one SSRI for the other. Does anybody know what the usual weaning off period for Citalopram is? (guess I feel the need for an exit strategy just in case!)

I do think I’ll give it a go; I’ve been on & off the Tamoxifen so much that anything that can help to keep me on it consistently must be a bonus!

Good luck with the Effexor. Really like to hear how you get on as well!