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Brain Fog and Cognitive Effects



  • hoisholt
    hoisholt Member Posts: 9

    Yes, my memory has really gone haywire. Unbelievable how much I forget. It can be embarrassing and it seems to have gotten worse in the last six months. I'm sure there is not a pill to take but any thoughts on how to, at least, manage the darn phenomenon. Besides writing down every conversation one has. I gave my daughter and son in law a gift for the future and told them to keep my card so when I am aghast at the cost of my gift they can show me the gift card. Ha!

    There must be methods of memory recapture for people who have a form of dementia. Can those treatments benefit our brain misadventures? Google it I guess

    Let's all agree 2200 will be our good year.

  • murfy
    murfy Member Posts: 252

    Moveforward, exercise has been shown to help with memory in women with low estrogen (menopause and/or surgery or drug-induced). It does this by increasing blood/oxygen flow to brain, improving sleep, and by increasing circulating levels of the protein BDNF that has been shown to increase new brain synapse formation in the absence of estrogen.

    DebAl, I remember researching AIs ad nauseam before picking one. Their actions were comparable, but exemestane seemed to have less severe SEs according to the literature. I actually chose it because of its steroid structure as that seemed more 'natural' compared to the others. I then tried different generics and found the Walgreen's brand to be most tolerable. My new mantra...only 14 more months!

  • threetree
    threetree Member Posts: 1,017

    Murfy - Interesting and helpful overall info, thanks for noting. Interesting too that you chose exemestane because it is a steroid. I take Letrozole and have yet to try switching to anything else, in spite of awful side effects, but I have thought that exemestane would be an absolute last resort because of it being a steroid. Steroids and me have never gotten along! I've come across some doctors over the years who hand them out like candy. Why is it that you consider a steroid more "natural" so to speak?

  • murfy
    murfy Member Posts: 252

    Threetree, exemestane is a synthetic steroid that binds irreversibly to aromatase, thus preventing natural steroids from binding and being converted into estrogens. Exemestane does not bind to ER or have estrogenic effects; however, it might have weak androgen effects, especially in large doses. So, that it is a steroid and binds to the steroid-binding site on aromatase seemed 'natural' to me and may contribute to its being more tolerable.

  • sarahsmilesatme
    sarahsmilesatme Member Posts: 52

    Thank you for this post! I’ve been taking Letrozole for almost 2 years. I was (and am) grateful that my side effects have been minimal; however, for the past several months, I have also noticed that I have trouble recalling things - words, events, details. I also “second guess” my decisions to the point of driving myself (and my husband) nuts. Murfy - interesting info re: the positive impact exercise. Yet another reason for me to get moving.
    Thank you.

  • threetree
    threetree Member Posts: 1,017

    Murfy - Thanks very much for the info, it's helpful. If I decide to try and switch at some point, I will look into this some more.

    SarahSmiles - I've been taking Letrozole for 2 years now also, and I have trouble with memory and decision making too, along with all the aches and pains, etc. It's driving me crazy and I just don't know what the answer is! For now I just trudge on through the muck and long for the day when I can stop this damned pill!

  • racheldog
    racheldog Member Posts: 209

    There definitely are (recent) articles coming online about how AI drugs have an adverse affect on the brain and cause cognition issues. More studies are needed on this. I have definitely noticed a difference in brain fog, sleepiness, and "just not right" feeling in my head. Like I want to shake my head free to clear my mind! I have always been sharp as a tack with good memory and no impairment so this is scaring me to endure these awful drugs too much longer.

  • murfy
    murfy Member Posts: 252

    My initial plan had been to stay on AI treatment for only 5yrs, after my doc suggested that I would be a candidate for 10yrs. Turns out I gave AI treatment only 4 yrs. I saw my MO this spring and I told him the brain fog was intolerable. Because of my age and my family history with dementia, he supported my decision to go off AI as of 4/1. And I can report that just 1mo later, my brain fog is gone. Interestingly, my joint pain is only slowly improving, but the brain normalized pretty quickly and I haven't had a UTI since going off the pills. I weighed my pros and cons and came to the grim realization that I would rather risk dying from a BC recurrence than losing my mind. But, the good news here is that brain fog and cognitive issues appear to be reversible upon cessation of AI use.

  • binwa
    binwa Member Posts: 5

    Murfy, Thank you for your post. I've been on letrozole for 5 years and just was told I can stop it. Yay! I've had all the listed symptoms but the cognitive stuff has been the worst to deal with. You just gave me hope it will get better soon. Thanks agai

  • sallyred
    sallyred Member Posts: 23

    I've only been on the full dose of anastrozole for about a month, and am already concerned about brain fog. It's the one side effect of an estrogen-blocker that my MO didn't talk about. Like you, racheldog, I find it pretty scary. I can't tell yet whether the ankle (and now knee) issues I'm having are related to the drug or just the occasional aches that come with life. But the best thing I'm aware of for getting more blood flow in the brain (to compensate for what estrogen would do) is exercise. Right now I am hobbling around and realistically can't do much walking. This too shall pass ... hopefully before my 5-7+ years on the hormone blocker ends!

  • racheldog
    racheldog Member Posts: 209

    Sallyred, I relate to you and knee pain, etc. Except I know I need a 2nd knee replacement. This cognitive business and brain fog scares me as I have always been sharp as a tack mentally. A past good multitasker and now I feel like my world has just slowed down to a crawl somedays where I have to make sure to think things out. I just feel like a need to give my head a good shaking out to make it clear. Head just feels "full" and it is hard to explain? I have been on Letrozole every other day for 1.5 months and I cannot see living like this for 5 more years. Today I got my 4th vaccine (2nd booster) and I am skipping the AI tonight. There are just times (like next week when I have to attend a family funeral) that I refuse to take the AI drug so as not to seem like I am not able to think clearly at an event. Hard to plan a life like this.

    Of course this is also taking me to some dark places and thoughts sometimes like ...what if this is brain mets? Hard to not think about recurrances, etc. when you are just not like your old self and treatment is done.

  • katg
    katg Member Posts: 193

    I have only been on letrozole for 3 months, but i definitely have cognitive issues. I was not sure if it was chemo fog. Forgetting names. I just start messaging someone and need to look it up again. Google a place then try again and i cannot recall the name! I hope it does not get worse.

  • moderators
    moderators Posts: 7,199

    Hello, all,

    We wanted to let you know we have organized a new meet-up for people age 45 and under with a metastatic breast cancer diagnosis and wanted to let you know in case you would be interested in participating if this meet-up description applies to you. The meet-up will be run by Julie Kramer, who had a metastatic diagnosis of sarcoma in her 20s.

    Under 45 w/ Metastatic Breast Cancer

    When: Thursdays at 1pm, ET (first meetup is May 26, 2022 1:00 PM Eastern Time (US and Canada)

    Register in advance for this meeting:

    We hope to see you next Thursday, and please share with others who may be interested in being part.

    -- The Mods

  • threetree
    threetree Member Posts: 1,017

    Why is this posted in the brain fog and cognitive problems from hormone therapy thread? Shouldn't it be in the metastatic threads?

  • oldladyblue
    oldladyblue Member Posts: 289

    I just found this thread and feel I fit in here for sure. Brain fog from chemo, rads, covid, and then from Anastrazole, ugh. Pre-chemo last year, despite being senior citizen, I had great memory, and a very detail oriented mind. The loss of "brain power" from cancer treatment has been very frustrating. Two weeks ago I went off of Anastrazole as there were many other side effects also, but I know that my brain fog is lifting. I have been taking a course since April that requires some intensive studying, and the difference between studying on the AI and off of the AI is huge. Today I see my doc who will probably prescribe another type of Estrogen suppression, but if it suppresses my brain and body functions like Anastrazole did, I don't think I can take it.

  • racheldog
    racheldog Member Posts: 209

    Today, June 1, I am going to try to go back on Letrozole every other day. That was enough side effects for me. I stopped for the past two weeks because I wanted to have my brain back for a family function. The fog has lifted a lot. My onc gave me Anastrole to try but I am going to try Letrozole again. If I feel the same, I may try Anastrozole but doubt any changes will happen.

    I am headed for knee replacement in August and I will not be on these dang drugs during rehab. In my heart, I still think the toxicities of these AI drugs outweigh the benefits for 5 years of them doing hell to our bodies. I am older, too, and live alone. I need to be able to take care of myself.

  • noey69
    noey69 Member Posts: 20

    Brain Fog. I'm terrified of starting my AIs.

    It's definitely something I have been struggling with for some time. I am 53 now and was diagnosed in February. However, my brain fog started about 4-5 years ago. I am a teacher and I can remember sitting in my principal's office crying because I felt so ineffective and "dumb"- just not myself and not able to remember everything like I used to. I was attributing it up to lack of sleep - which has always been a chronic issue for me. At my next gyno appointment, my Dr. started asking me questions about menopausal symptoms - she named brain fog as a symptom. That was the first I knew about estrogen's power. I was having night sweats and other minor symptoms - but to hear that there was something that could fix my sleep problems and fog! I was sold. I started HRT. After a couple of months, my night sweats diminished, my fog lifted, and my sleep even improved (after raising progesterone dosage to 200mg/ day).

    Fast forward (again) to Feb. 2022 when I was shocked to be diagnosed with BC. Stopped HRT immediately, had lumpectomy in April, currently in radiation.

    I have not started AI pills, but my brain fog is already back. I'm so worried that it is going to get worse once I start to take them. I've also started to experience daily headaches and issues with urination urgency since stopping HRT.

    I exercise daily - I have for years and years (even running multiple marathons over the past 10 years). I eat well, don't smoke, only occasionally drink, healthy weight, etc, etc, etc. I do (and have been doing) all of things that are supposed to prevent problems.

    All I can picture for myself right now is wearing diapers and not knowing my name.

    I'm too young for that! :(

    I will be starting my pills in two weeks. I will give them a try. Fingers crossed that nothing gets worse.

  • sallyred
    sallyred Member Posts: 23

    Noey69, brain fog is my biggest fear and current side effect with the anastrozole, too. I've been on it since mid-March, and have been having trouble focusing and concentrating. I know the daily radiation appointments don't help - even though they are short and in the mornings, they disrupt my day and concentration too. My MO is pretty dismissive of this - the place where I'm feeling unsupported by him. I've mentioned the possibility of adult ADD, and that's his go-to explanation. Maybe. But I'm *tired* of doctors and medications, and doubt I'll pursue finding out if it could be ADD for now - I was going to say I just wanted to go back to normal but the old "normal" seems to be gone forever. So, I want to start my new normal, and see whether finally getting away from daily and weekly appointments will allow me to settle into a routine.

    My RO says that it is the body's adjustment to the changing hormone levels that causes the brain fog, and that will dissipate over time. I forgot (haha) to ask my MO about that, but I have friends who had terrible brain fog when first going through menopause, and are back to being sharp cookies now - so hoping that there's truth in that explanation. It's hard to tell from this group whether that could be the case.

    Good luck regardless!

  • threetree
    threetree Member Posts: 1,017

    Sallyred - Some of these issues with side effects are not "adjustments" that will disappear over time. I've had brain fog since I started Letrozole 2.5 years ago and it has never let up, along with other side effects that I was told would go away eventually. I've given up trying to talk to these doctors about the side effects. They dismiss them, or tell you it will eventually go away (yeah, right), or they want to give you the old "we've got another pill for that" re side effects, and then your doing the pill for the side effects of the pill for the side effects of the pill ...... thing. I'm going to put up with this stuff as long and as best I can or just quit and take my chances. I'm trying to pull back on talking to doctors about a lot of this stuff and I'm trying to minimize appointments now too. It can all become a rat race and vicious cycle. I'm trying to tailor things more and learn when I really need those people and their pills, and when I don't.

  • 5kmc
    5kmc Member Posts: 11

    Ok this is where I need to be!!! Have only taken AI for 5 wks and the last week was hell!! Not so much brain fog for me, but I cried for a wk for no reason, was mad at everyone and everything and didn't want to do anything!! My husband looked at me and said, "5 years?" and he is the most patient human on earth!! And the aches and pains were awful!! It was menopause all over again, been there done that. So I haven't had a pill since sat and today feel myself. Worked in my yard all weekend even in the heat! Felt so good. Probably gonna stay off till my appt on 7/12 and see if I can get any cooperation on making this eaiser. Hve a feeling I'll get the "oh these symptoms will dissipate over time" speech.

    Really feel more empowered and more ready to advocate after being here!!!

  • choochoobella
    choochoobella Member Posts: 25

    I worry about cognitive loss too. I'll have completed ten years of Letrozole next March (2023) and will go off it then.

    I feel like I'm tolerating Letrozole more now than in the early years when I had more roving joint pain. I still move like a 90 year old at times, but I try to stay as active as I can and that helps. My dexa scans show significant decreases in bone density while on Femara, although I'm not quite in the osteoporosis range yet, only osteopenia.

    I try to think about cancer as little as possible. I've lost my breasts, gynecological organs, thyroid, and parathyroid glands to cancer and that was okay with me. But my brain - it's my favorite organ. I work hard on my memory. I used to be an ACT/SAT tutor and I still take a timed ACT or SAT test every week to try to keep my math, English, reading comprehension and science skills sharp. I work on my vocabulary skills on a website called I started refreshing my Italian language skills a few months ago by doing Duolingo at least 2 hours a day. I took Italian language courses back in college for 2 years, but that was 45 years ago. I see it all as exercise for my brain.

    I feel consoled by friends who have never had breast cancer, but feel plenty of brain fog after menopause (can't remember names and other nouns, forget why they entered a room, need to write lists for everything). It's hard to know how much is due to natural aging and how much is due to hormonal therapy. Because it makes me feel better to think so, I chalk up any brain fog to aging. Still, I completely respect anyone's decision to stop hormonal treatment if the side effects are too much. We each have to choose our own path.

  • mikamika
    mikamika Member Posts: 242

    I read an interview with a neurosurgeon, and he mentioned that learning something new helps our brain build cells. He emphasized NEW knowledge, and not solving puzzles. And also walking is beneficial. So I am trying to follow his advice.

  • lillyishere
    lillyishere Member Posts: 757

    I am bilingual. I can't remember anything. How can I learn a third language when I can't remember the ones I know? Maybe I should start re-learning my primary languages :)). For real, losing memory is a scary thing. I can barely perform my job and other basic tasks. I get tired even scrolling through Instagram pictures. I wonder if these AI meds have long time effects on increasing risk of dementia.

  • mikamika
    mikamika Member Posts: 242

    Hi Lilly, how are you doing? How is your experience with Aromasine?

    Learning a new language or professional skill is a really good idea. But I was talking about the smaller things: learning how to cook a new dish, learning how to take care of the new plant, etc. For example, I know how to cook rice but I've never cooked cilantro lime rice. So, I will do it today. Yes, I agree with you that AI treatment is really harsh and toxic. And there's no support from my health care team.

  • mikamika
    mikamika Member Posts: 242

    Well, tomorrow I will try those "speed-processing games". :)

  • WC3
    WC3 Member Posts: 658


    That happened to me the first few weeks I was on Tamoxifen. It made me very uncharacteristically emotional. One of my sisters said something that sounded kind of harsh to me and even though I knew she didn't mean it to be and it typically would not have upset me, I had a good cry after we hung up the phone. I'm now on Exemestane/Aromasin and apparently, according to my friend, it makes me "grumpy." It does. I wasn't so agitated on anastrazole but the joint pain and discomfort got to be too much. Exemestane seems to give me more back soreness but not nearly as much discomfort in my other joints.

  • sallyred
    sallyred Member Posts: 23

    Threetree - I am afraid you're right that the brain fog isn't a short-term adjustment, and I'm sorry you've had to put up with it for so long - with more time yet to come! I get no comfort from "SE disappear after you end the course" since my brain will be 7 years older by then (and I'm working and thinking NOW). I also agree it's frustrating when the answer to a SE is a pill - with another SE - and on and on. This is where "modern" medicine seems a real failure to me.

    My PCP is of a different ilk, and I'm on the fence between learning more from the research he's pointing me towards (including how estrogen and other hormones are essential in preventing cancers) and trying to stay the course for awhile longer. Amazing to me that, with the high percentage of women/people abandoning hormone blockers and risking recurrence that there aren't more attempts at a new approach. I guess I'm thinking "problem solving" and not "status quo" and "profit." That sounds a bit harsh, but -?

  • threetree
    threetree Member Posts: 1,017

    SallyRed - I agree with you wholeheartedly about all of this. Yes, we need our estrogen for all sorts of bodily processes, and without it we are a mess.

    After your first post in which you mentioned the cognitive side effects, I looked around for an article/study I'd read on the internet a year or so ago about that issue, but I couldn't find it to post here. We are told that these cognitive side effects will go away when we are done with the pill, and that our brains will return to normal, but the study I read said that that part about our brains returning to normal remains an open question. The study looked at the cognitive effects and said that what the lack of estrogen in our brains does is very similar to what it does in dementia. They noted that most seem fine again after finishing the drug course, but they said that the mechanisms for getting dementia sooner, rather than later, could be set in place, by virtue of having taken the drug, and that it is of course something that would require further study. This was the first thing that I've read that did not simply stop at the idea that once your done with the drug you go back to normal. These researchers seemed to see a possibility that these AI's could set you up for getting dementia down the line; dementia that you would not have gotten otherwise.

    I'm going to continue trying to find out more about this issue, but I also continue taking this stupid pill every other day, not knowing if I'm really doing the right thing or not. The doctors I see only have one viewpoint and that is to take this Letrozole at 2.5 mg every single day or switch to another estrogen lowering drug. I don't want to do either.

  • mpetago
    mpetago Member Posts: 46

    I've gone a bit rogue in this respect. I was 35 at diagnosis (now 54) and took tamoxifen for five years. Definitely had side effects including brain fog, joint and bone pain, which I assumed to be chemo brain, hectic life, stress, etc. Within a few weeks of being off tamoxifen, it was like a heavy veil lifted and I felt amazing. Lost weight effortlessly and just felt like myself again. I decided against having oophorectomy because I wasn't willing to have that quality of life going in to instant, permanent menopause.

    I assumed, wrongly, that if I made it to menopause I would have a more gradual and gentle tapering off estrogen and it would be easier. Wrong! Started in earnest about three years ago and I recently just fell off a cliff, going in to the most extreme depression and brain fog imaginable. Anti depressants and positive attitude are doing nothing, and I finally realized that it's ALL due to the lack of estrogen. Everything I've been experiencing is from lack of estrogen, during treatment and now. I had no idea until I started researching it in desperation recently how vast the effects of menopause can be on our health, especially mental health.

    I stood in my driveway for about ten minutes last week unsure which car I was supposed to drive to the airport. I know it may sound crazy, but I am going to try HRT. I've been doing quite a bit of research in this area and am willing to take the risk because this is no life. An oncologist Dr Bluming has recently published in Cancer Journal about HRT for breast cancer survivors, I can email a copy to anyone who is interested. He coauthored the book Estrogen Matters and has also spoken about this in podcasts online. That book argued that the study (WHI) that linked HRT with increased breast cancer risk was flawed and has been walked back many times since its publication in 2002 to the great detriment of menopausal women who have needlessly avoided HRT since, despite its' proven reduction of heart disease, bone fractures and dementia - the top three killers of women.

    It goes against everything we've been told, but the reality is that doctors still don't know what causes cancer, and what role estrogen plays, why or how. Obviously none of us want a recurrence if possible, but there are just no guarantees. I am not willing to have this low quality of life just to die from breaking my hip in a few years due to no estrogen. Something is going to take me out, and this menopausal depression will do it sooner than anything else. I just think I have to be willing to consider all research, particularly when we know how very little has been done with respect to women's health and hormones.

  • sallyred
    sallyred Member Posts: 23

    Thanks for the book recommendation, mpetago. I was on bioidentical HRT for years - and I am NOT convinced that it is the cause of my breast cancer. I found my MO's staff (and the MO who was my second opinion) alarmingly ignorant of the difference between synthetic HRT and bioidentical HRT. And I'm still in the camp of - estrogen is one of the things that defines me; stripping it from my system is nuts!

    And I'm still taking Anastrozole every day ...