Antidepressants and tamoxifen

Could anyone tell me which antidepressants are safe to take with tamoxifen.
I was prescribed zoloft by my gp today, came home and googled it and this seems to be one that you shouldn’t take with tamoxifen.

Think you should have a chat with onc or bcn to check it out. I know that prozac/fluoxetine and tamoxifen is a no-no but can’t tell you which ADs are ok though - good luck!

Hi beardie

I know Fluoxetine (Prozac) is NOT safe because how it is metabolised in the body reduces the effectiveness of Tamoxifen, but it’s only in looking for further information this evening I have found that Paroxetine, Sertraline (aka Zoloft!) and Bupropion are not recommended, nor is Duloxetine.

It’s not DANGEROUS for you, just kind of defeats the purpose of taking Tam. If you want to get techie, it’s to do with “cytochrome P450 2D6 (CYP2D6) inhibitors”. Tamoxifen is metabolised by cytochrom P450 enzymes, so if you take something that inhibits these enzymes, you reduce the effectiveness of Tamoxifen.

Some of the more modern SSRIs and SNRIs that are much safer are Venlafaxine, Mirtazepine and Citalopram, there may be others. These are also sometimes prescribed to help reduce hot flushes, so have two uses. Also sometimes prescribed are Amitryptiline which is a tricyclic anti-d, and I am under the impression that tricyclics don’t have any effect on CYP2D6 enzymes.

Whichever you are prescribed, your GP should be looking them up in the “little book” that all GPs have which lists drug interactions, so any time you’re prescribed anything, make sure they look it up, just in case.


I found out this information by looking at the AscoPost, dated 15th Nov 2011, if you want to look at all the techie references in the article, and then got completely side-tracked reading lots of other articles…

Thanks choccieMuffin - going to call onco this morning see what they say - well i will leave a message and wait and see if they ever get back to me. Thanks again x

Mirtazapine def ok (according to my gp) though i wouldn’t recommended it as it turns you into a zombie and makes your legs restless! Or at least, that’s what it does for me…

Like choccie and JulieD say, Prozac isn’t recommended as it makes tamoxifen less effective. Didn’t know about those other ones though so thanks choccie for that info (for when I’ve had enough of the zombie-phase and want to try something else!).

Hope you find something that suits you and doesn’t affect tamoxifen beardie.

Al x

I hope tam and prozac work together. Just taken my first one!

Anyone on tamoxifen and fluoxetine or paroxetine should definitely query this with their doctor. One study showed a definite increase in death with tamoxifen and paroxetine (i,e, the tamoxifen did not work as well as it should have) but not other SSRIs (the class of antidepressant).

The theory behind this has led to doctors being told not to prescribe either fluoxetine or paroxetine - they were sent an alert last year and it now appears in the BNF (doctor’s bible) so no excuses.

Other SSRIs are more problematic as no studies to test this, but the theory of drug metabolism makes some more likely to have a problem than others, but this is best guess stuff.

Sue - a pharmacist - I got the GPs I work with to search for pts on this combo when the alert came out and now every three months to look to see if any pts have slipped through the net.

Bloody hell. I only saw the gp two hours ago.

In which case, elttiks, one Prozac won’t do any harm in the grand scheme of things, but you should (imho) call the surgery and get yourself an emergency appointment with your GP for tomorrow and take in a bit of information for him or her.

The site I mentioned is so take a look at that, and if it doesn’t print out on too many pages, take it with you. I know it’s an American site, but it’s the news stuff for clinical oncologists, and contains proper references to the research that has been done, so is a bit more trustworthy than some sites you might visit…

One caution, I spent ages browsing last night, there are so many INTERESTING articles on there, I completely lost track of time!

Hi all,

Just got back from my GP’s office I asked if he could put me on Citalopram for the hot flushes and for the moods, he is going to speak with my onc. and see what he says. My GP was not keen on giving me this anti-depressant as he feels it might compromise tamoxifens efficiency.
ChoccieMuffin is right about the enzyme and the metabolism of tamoxifen but my GP seemed to think that the Citalopram does have an effect on the enzyme CYP2D6. Anyway I am now waiting for my GP to call me back after he’s spoken with my onc. I shall keep you all posted. Thanks to chocciemuffin for pointing the enzyme thing out, I’m just not academic at all and get so confused with all of this.

Sending love and llight to all
Sarahlousie xxx

Prozac now returned to chemist. Citalopram to be collected tomorrow.
Was told the chance of interation was almost zilch. None of the labels said anything either, nor the pharmacist.
No harm done. Glad I spotted this, cheers Choccie.

SL, take a quick squint at the link I posted earlier. There’s a table that lists those with high, medium, low and no interaction with the enzyme thingies, and Citalopram’s one of the low ones, whereas Prozac’s one of the high ones. I had Prozac several years ago and it worked well for me, Citalopram seems to be doing ok for the flushes (still there but not quite as severe as they had been) and have definitely lightened my mood.

If you do start with one and find you don’t get on with it (there are some other side-effects from the various anti-d’s that sometimes affect some people) it’s nice to know that there are others you can try that might agree with you better.

I passed a loose outline to one of the ladies in our FB group. I hope she can gain some knowledge in this too.

At diagnosis I was put on Citalopram 20mg because I was already feeling very very low due to miscarriage, fertility treatments, employment issues and problems we were having.

This week my doctor has upped it to 30mg as I’m having some anxiety - I’m thinking after all the chemicals I’ve had that this isn’t something to be too worried about.

Citalopram is safe to use with Tamoxifen apparently and is often used to help menopausal symptoms as a result of it too.


Yes - I take it at a 10mg dose for hot flushes, and I am on tamoxifen too.

has anyone any experience or advice on the AD trazodone? been prescribed this today(50mg) for mild anxiety and sleeplessness due to horrid night sweats. been on tam for 7 months. my naive googling(bad i know) puts it as a middling AD. just dont want anything to comprimise tams job! as you can prob tell, dont have a great faith in my gp! thanks in advance alex xx ps currently awaiting a call back from mt bcn re the above)

Changed mine today and made a start. 10mg’ll do nicely. Add the anti d’s to the anti b’s and the beta blockers. Surely normallity is out there somewhere?

Elttiks - I know the teeth grinding, stomach churning reality of bad anxiety at the moment. Seriously considering asking them about beta blockers… I had some a few years ago due to anxiety and they were amazing help.

MB, haven’t ever heard of that one, but I’m no expert.

Elttiks, welcome to the ‘new normal’…

thanks CM. my BCN says no. BCC lovely lady on helpline wouldnt commit but i got the gist. blooming maddening and confusing aint it??? alex xx