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Tamoxifen and Anxiety/Anti depressants - Help!

mdg Member Posts: 1,468

I am having issues getting medications to help me with all of this BC crap.  I have always been completely type A and a worrier so getting BC really didn't help my cause!   I have been on tamoxifen since last June and of course have the hot flashes.  I have been taking xanax at night since last March to help calm me down so I could sleep at night.  I tried ambien, but that did not work.  The xanax helps me relax so I can fall asleep.  I was being consumed with worry so in October my internist started me on Lexapro.  After a few weeks on it, I felt great and was sleeping really sound (better than before being on it).  I was not worried and was mellow.  I was still taking xanax before bed and all was good.  I went to a med onc appointment and he said he did not want me on lexapro and insisted my internist change me to effexor as it does not have potential to interact with tamoxifen.  I went back to the internist and she helped me make the switch.  The effexor is NOT working and since I have been on it I have active, disturbing, realistic dreams ALL NIGHT LONG!  I wake up a lot.  I have more night sweats and chills.  I can't fall asleep - I am wired on it not matter if I take it in the morning or before bed.  It has been almost two months and I am exhausted.  I don't get any restful sleep.  I can't live like this anymore.  My internist says she will put me back on lexapro (which med onc says no due to potential to interact with tammi) or keep me on effexor and take me off xanax and give me sleeping pills.  I DO NOT want to take sleeping pills.  The effexor is making me tense anyway...I don't feel relaxed EVER.  I hate it.  What meds do you take if you are on tamoxifen?  Any advice appreciated.  I am so tired and stressed. 



  • coraleliz
    coraleliz Member Posts: 158

    Ask your MO about a SERM called Toremifene. I've read about women going that route in order to stay on an antidepressent that worked well for them.

  • calilisa
    calilisa Member Posts: 5

    mdg - I'll be interested in seeing the responses to your question.  I was prescribed lexapro by my pcp while on tamoxifen, and my oncologist said that it was ok.  This is all so confusing. 

  • Rennasus
    Rennasus Member Posts: 642

    Maria, I'm also interested to see what others say about this topic. Thanks for posting this!

  • Kadia
    Kadia Member Posts: 25

    As a person with lifelong anxiety, I can empathize. It is critical to let your mo know how much the anxiety is impacting your life and that the Effexor is not working,whereas the lexapro did. I personally would insist on taking the med that works for the anxiety, even if there is a chance it may have impact on the tamoxifen (which I think is still a very open question).

    As for Xanax, since it can be habit forming, I agree with your doc that an alternative would be better. It is best to use benzodiazepines short term only. You may not need a powerul sleeping pill if you practice really good sleep hygiene (rules about bedtime routines, foods and drinks to avoid, Etc.) and use a milder sleep aid. I use melatonin and trazodone, which don't knock you out, but do help with sleep. Ask your doc about trazodone. It's actually an antidepressant, and can help with anxiety, too. I take a low dose at night only.

  • trotterc
    trotterc Member Posts: 1
    I have been on Anastrozole & exemestane and have had awful side effects.  I am asking for another option for estrogen suppression.  I was so depressed and the dizzy vertigo effect.  Hot flashes and pain in the bones and joints I could handle.  So I really feel for you.  Lack of sleep is so hard on us.  My body is just not compatable with the first two.  I am stage 1 no lymph nodes involved.  Just estrogen positive.
  • besa
    besa Member Posts: 283

     This is is from "Pharmacist's letter's"  and talks about SSRI - tamoxifen drug interactions.  It was published when the FDA decided to add warnings about these drug interactions. 

     From Pharmacist's Letter's: July 2009, vol 25, no. 7 

    "You'll see new warnings not to combine tamoxifen
    with certain SSRIs..paroxetine, fluoxetine, and sertraline. .... Women
    have a higher risk of breast cancer recurrence if they take tamoxifen
    along with paroxetine, fluoxetine, or sertraline... but NOT citalopram,
    escitalopram, or fluvoxamine. .....About 30% of women on tamoxifen also take an SSRI for depression or hot flashes.   FDA will add new warnings..and Medco is alerting physicians if a woman on tamoxifen
    gets paroxetine, fluoxetine, or sertraline.   Suggest using one of the
    other SSRIs or venlafaxine if needed for depression or hot flashes."

    My understanding is that Lexapro is the same as escitalopram .  This article says is still OK to use Lexapro with tamoxifen.
      (citalopram =Celexa, escitalopram=Lexapro, fluvoxamine = Lupox are OK)
      According to the article  "paroxetine, fluoxetine, and sertraline are
    stronger 2D6 inhibitors than the other SSRI's" and they are the ones
    that are a problem in combination with Tamoxifen.  (peroxetine = Paxil,  fluoxetine=Prozac, and sertraline = Zoloft are NOT O.K.)

    I am not a physician and this is not medical advice but if  I am interpreting this correctly you might want to talk to a pharmacist about this drug interaction (try to find a pharmD) and also show this article to your MO and ask him/her about the reasoning behind this decision.

  • Cherilynn64
    Cherilynn64 Member Posts: 156

    Hi MDG and others,

     I'm a pharmacist and just found this so happy to help you.

    Techincaily you can be on Lexapro and tamoxifen together. Lexapro and Effexor are both weak CYP2D6 inhibitors of tamoxifen and hence why they don't have the interaction potential that the strong and modearte CY2D6 inhibitors do. Benadryl is a moderate CYP2D6 and I saw a woman who had posted on another forum page that she is on tamofixen and takes benadryl every night to sleep, and I jumped in "Noooooo!" LOL. Because it's OTC med, if she didn't tell her pharmacst that she was taking it when she started tamoxifen, she wouldn't have been told to watch it with that. Same as with OTC Tagamet.

    CYP2D6 is the enzyme in your body requied to make tamoxifen convert to endoxifen which is the actual active med that works to block hormone receptors. So for tamoxifen to do it's job in your body, you need to not be on a med that stops that enzyme from working, called inhibitors.

    I found this very basic list frmo IUPUI which is coincidentally the first hospital I worked for after graduating college in 1988. Total coindicence! It's a pdf that you can print and take to your doctor and show that Lexpro is ok to take.  

    This is not a complete list - there are a LOT of CYP2D6 enzyme inhibitor meds out there. Also, Lexapro and Effexor for that matter ARE weak inhibitors....very weak so they are on the "non-inhibitor" list. But everyone is different, and some people metabolize better than others, too. It would be a good idea for anyone who needs to be on any antidepressant to never take it at the same time as tamoxifen. If you need the slee effect of the antidepressant that works for you, then take that at night and take tamoxifen in the morning. But techinically Lexapro is ok. and 2D6v7.pdf

    Besa I'm curious, RPh Letter is a paid for subscritpion for us, how did you get access to it? It's not supossed to be for the public, but I'm glad you found the info to post. Plus for the fact they charge us for it, LOL!


    MRDRN Member Posts: 177


    Thanks for your information and I appreciate this thread.  I too did not do well on effexor longer term as I got headaches as I recall.  Cheri what do you think of Gabepentin often prescribed for Hot Flashes?

  • besa
    besa Member Posts: 283

    cherilynn64- I do technical work and have access to many journals and reports.  In addition, the National Libraby of Medicine is a wonderful resource for anyone in the DC metro area who wants to see the full text of journal articles ("Pharmacist's Letters" - included). 

     I like the 2005 "Journal of Oncology Practice"  article by Frankie Homes et al  which I think is very well written and explains clearly the potential interaction between strong SSRIs and tamoxifen.

    "Pharmacogenomics of Tamoxifen in a Nutshell-And Who Broke the Nutcracker?"

  • Cherilynn64
    Cherilynn64 Member Posts: 156

    Hi MRDRN,

    Gabaentin for hot flashes is still "off label" use but I know it's gaining in populatiry b/c of all the studies that show it as effective as estrogen replacement and the SSRIs and similar classes currently used. Gaba really started taking off a few years back for restless legs syndrome and for peripheral neuropathy in type 2 diabetics. And it's been used for years and years for migraine prophylaxis. From what I know the exact mechanism of why gaba works so well for hot flashes is "the jury is still out" response b/c it works in several different ways. It's overall a good drug and although it does require titrating up to a dose normally, once you're stable you're usually good to go. Can have a lot of neurogical effects at first as you would be using an anti seizure med, but for that indication patients usually have to keep ramping up their doses and are monitored for clinical effectiveness and side effects. For all the non-seizure uses it has been used for in the past and current new uses, the doses don't need to be as high and therefore once at stable dose, that's the dose you stay on. And the neuro effects tend to go away after you've been on it for some time.

    The SSRIs I'm just not a huge fan of....for certain medical conditiions, they were a Godsend when they first came out (I was at the end of college when Prozac hit the market). And for many people they are still a Godsend and very necsessary. For the general population they are way over prescribed. And you're dealing with your brain chemistry and you have to be careful when starting and stopping these meds (they require a tapered dosing). And with so many now in the same class, finding the exact one that works for you can be a lot of trial and error. And they're not without their side effects, some really nasty. 

    If you find an SSRI or similar that works for you and doesn't interfere with tamox, stay on it. If you are bouncing from one to another due to side effects or not working, I'd ask your doc what he/she thinks about trying gabapentin. It seems to be doing a really good job for a lot of women. 

  • Cherilynn64
    Cherilynn64 Member Posts: 156

    Besa, thanks for that article link! I have read that journal on occasion oniine when browsing for info. Yeah that article was back in 2005 after we got the big "uh oh, look what paroexetine is doing with tamoxifen" news. That article is really well written - thanks for sharing it!

  • SusansGarden
    SusansGarden Member Posts: 754

    Cherilynn64 ~ So this discussion makes me curious to know your opinion on the CY2D6 the time of my medical onc had just got back from the 2010 San Antonio breast conference where they released a new study saying that the test was no longer being recommended because research was showing no difference in (recurrence or survival - I can't remember) rates between poor metabolizers and extensive metabolizers.  So therefore, why take the test if it wouldn't change the fact that he would still prescribe the tamoxifen either way? 

    I ended up asking my naturopathic onc to test me.  Just for piece of mind.  I am highly ER+ and was thinking that if I wasn't a good metabolizer, I might need to look at other options like shutting down my ovaries and taking an AI.  Turns out I'm an extensive metabolizer so I'm one year into taking the Tamoxifen.

    The argument of whether or not you're a good metabolizer not making a difference doesn't make sense to me?  If Tamoxifen doesn't "work" until your liver metabolizes it...then doesn't that make a HUGE difference??  If it didn't make a difference, than why would we even care about other meds interfering?

  • momoschki
    momoschki Member Posts: 218

    You might consider Wellbutrin, which is not metabolized through the CYP2D6 pathway at all.  This has helped me considerably to not feel on the brink of hysteria all the time.  I do take Klonopin to sleep, despite its addictive qualities-- I barely slept before all this BC nonsense, so I cannot imagine that I would make it through the night with some modicum of decent sleep without it.  It doesn't work as well as it did a year ago, but I am careful not to ever up the dosage.

  • SelenaWolf
    SelenaWolf Member Posts: 231

    My question is... is raging insomnia the side effect of all the drugs or the fact that some of the drugs we've all be on during treatment throw us into menopause?  Or both?

  • NJvictoria
    NJvictoria Member Posts: 45

    Hi Robo47,

    3 AM seems to be "my special time" to wake up every. single. night! So, I lay there and toss and turn and then finally after an hour or so, I finally fall back to sleep. So far, I don't feel worn out or anything. I don't work so I do have the luxury of napping if I need to, but I really haven't felt the need yet.

    I'm sure it's the Tamoxifen and the Effexor that I'm on. 


  • momoschki
    momoschki Member Posts: 218

    In my case, I had pretty bad insomnia before I started taking any drugs at all-- difficulty falling asleep and staying asleep.  I was pretty much a walking zombie during the day.

  • mdg
    mdg Member Posts: 1,468

    Well ladies thanks for all the great information.  I did start dosing the effexor in the morning instead of night time.  I also am taking my xanax a bit earlier to allow it time to do it's thing. I also am turning computer off and lights out at 10pm with just the tv on.  THis has helped me relax more.  The past two nights I have slept better and have woken up more rested.  I am having the dreams but not as intense and I did not wake up as much.  I guess I will give it a few more days before I do anything.  I am going to look at this information and print it out so I can discuss it with my doctors. 

  • Rennasus
    Rennasus Member Posts: 642

    Momoschki: Wellbutrin interacts with Tamoxifen. It is a high-level interactor. I used to be on it, but when I went on Tammi, had to go off of it. They both compete with the same liver enzyme.

    MDG: YAY!

    ALL: I have found that Tamoxifen also has a bit of a revving SE which is why I take it in the morning. Re: Why we can't sleep... I think its both the drugs and the fact that we have plenty to worry about and keep us up! I always had trouble shutting off my brain but since BC, it is worse at times. Xanax helps.

  • besa
    besa Member Posts: 283

    Susangarden-  here is the link to the abstract from the 2010 San Antonio BC conference. They are suggesting that "Variants in drug targets and estrogen signaling pathways may be the
    genetic basis for patient variability in anti-estrogen risk versus benefit profiles." as opposed to differences in the CYP2D6 or UTG2B7 genotypes that control enzymes that process tamoxifen.

    Thursday, December 9, 2010 10:45 AM

    [S1-7] Lack of Correlation between Gene Variants in Tamoxifen Metabolizing Enymes with Primary Endpoints in the ATAC Trial.

  • Joanne_53
    Joanne_53 Member Posts: 714

    My doctor also took me off Wellbutrin and switched me to Effexor.

  • cmbear
    cmbear Member Posts: 674

    This has been quite the informational thread! My doc put me on Citalopram when I was first diagnosed--didn't start Tamox until almost a year later. Fortunately, it is an anti-d that doesn't conflict with Tamox. I also had used Ambien faithfully since day one (it seems to work for me) because sleep has not been my friend. In January, my insurance company decided that I didn't need to be on it any more so I went cold turkey. I also had quit my stressful job in November. between the two, its taken me till just a few weeks ago before I could sleep thru the night. Well, I still wake up occasionally, and it does take me FOREVER to fall asleep.(usually don't even think about bed until 1 or 2 am) but I actually have been sleeping almost 8 hours a night. Haven't done that in years!!!! I would like to think that I took out one of my major stressors--work-- and that has helped me immensely keep my mind clearer. I know that is not possible for everyone but I think we all have that one thing --besides BC of course--that makes us stress. Whether it be family, work, finances, school something is filling our brain with nasty thoughts. Add in all the different drugs we take. . . .

  • Cherilynn64
    Cherilynn64 Member Posts: 156

    Momoschicki - that is not correct info about Wellbutrin. It's at the top of the potency for CYP2D6 inhibtors. 

    In a nutshell, if you are tamoxifen, the 3 antidepressants that are best not to be on are:

    Paxil (paroexetine), Prozac (fluoxetine), and Wellbutrin (buproprion). 

    The moderates are Zoloft (sertraline), and Cymbalta (duloexetine). Also hooked up with this group are over the counter meds Tagamet (cimetidine) for stomach/acid/reflux/etc and Benadryl (diphenhydramine). If you need stomach acid med take Pepcid or Zantac. And be careful as Benadryl can be found in combo cold meds and sleep aids.

    The least enzyme inhibiting and therefore the best choices to be on for antidepressants is:

    Lexapro (escitalopram), Celexa (citalopram), and Effexor (venlefaxine).

    It's a pain, I know. Frown  

  • Cherilynn64
    Cherilynn64 Member Posts: 156

    Susansgarden and Besa:

    There is an update since then that was just posted online early March. There were 2 studies they are looking at, and both were POSTmenopausal women only. The first study followed women from 1998-2003. So you're looking at 10-15 yrs ago when the aromatase inhibitors were new/not available yet and only tamoxifen was being studied. So where does that leave us who are premenopausal?

    What's interesting is that the 2nd study showed that women who are extensive metabolizers DON'T have hot flashes.....which is completely contrary to what the prevailing theory has been that it's women who don't metabolize it are not getting hot flashes. So Susan I'm with you in the quandry - I started tamoxifen 3 weeks ago tomorrow and it's like I'm taking a placebo. I have had zero side effects. Am I just lucky? Poor metabolizer? Or perhaps now I'm an extensive metabolizer based on this study? I'm personally asking for the enzyme test at my follow up on the 29th. I'm just flat out curious at this point.

    You got results back that you are an extensive metabolizer - so do you have hot flashes or no?

    Here's the link to the current article from March 2012: 

  • besa
    besa Member Posts: 283

    Cherylynn64- Thanks for posting the link about extensive tamoxifen metabolizers and hot flashes - VERY interesting.  I am also someone who takes tamoxifen with zero hot flashes (but have other side effects of tamoxifen - some leg cramps (not very often)  and at one point an endometrial polyp that was attributed to tamoxifen).  I have been taking tamoxifen for over 4 years.  There are women who go through menopause naturally without any hot flashes- so I am assuming this means that in their case although estrogen levels are very low (very low receptor occupancy) -the low level  does not cause hot flashes.  I wonder if  we could possibly be dealing with the same lack of response.....   The lack of side effects could be caused by something unrelated to endoxifen level.  From my perspective the whole thing is still a black box. 

  • Cherilynn64
    Cherilynn64 Member Posts: 156

    And I had all my hormonal levels run back in September as part of my annual physical as at 47 I had never had those run and I wanted to know about where I stood. My levels are all still pretty high and still very premeopausal. So I was figuring the hot flashes would come pretty quickly, yet I'm as cold as ever! 

  • amycday
    amycday Member Posts: 1

    This is all very confusing to me. I've been on tamoxifen for almost 4 years, and taking very low dosages of Lexapro and Wellbutrin for the whole time.  (5 mg and 100 mg respectively)  Last week, my psychiatrist called me to say that the pharmacy sent her a notice re the impact of Wellbutrin on Tamox.  My oncologist never thought either drug was a problem with tamoxifen but now I'm going to contact him to discuss again. The psych said that lexapro had very low risk and wellbutrin was moderate but that I'm on a very low dose so it might not be a problem.  Was there a recent study making it clearer that Wellbutrin will inhibit effacacy of tamoxifen??

  • Joanne_53
    Joanne_53 Member Posts: 714

    I am not sure about a study -- amycday -- but I was on Wellbutrin and have been switched to Effexor because of the interaction -- according to what I see, the interaction is major

    I have attached the link ..

  • moderators
    moderators Posts: 7,681

    amycday, the information about tamoxifen on the main site also lists Wellbutrin under Medicines to avoid while taking tamoxifen, and explains why.

    The Mods

  • Cherilynn64
    Cherilynn64 Member Posts: 156

    Amy, Wellbutrin has always been a major issue with tamoxifen, and I'm glad one of my colleagues finally sent something to your psychiatrist. They should have done so years ago, argh.

    It's all due to the CYP2D6 matabolism pathway. Wellbutrin is one of the more potent inhibitors. Lots of the psych meds are and hence why it's so hard to get patients on the right one that works for them when they start tamoxifen. I hope that your psych can find the best alternative for you now.


  • SusansGarden
    SusansGarden Member Posts: 754

    Cherilynn64 ~ I just saw your response about extensive metabolizer and hot flashes.  I am an extensive metab, and have no hot flashes.  On few occasions I will wake up a "sweaty" ... but not enough to change clothes or anything. And this never happens during the day for me.  I've been on tamoxifen for about 14 months now and still no noticeable side effects.

    Did you ask about getting the CYP2D6 test yet? :)