I started Letrozole in August 23 after a left mastectomy due to invasive lobular breast cancer, stage 2, grade 2, also in 1/12 lymph nodes.
Despite taking daily cod liver oil plus Glucosamine with Chondroitin, exercising, and trying everything possible, the stiffness, carpal tunnel syndrome, and fatigue have finally made me decide to give up as my quality of life has been impacted so badly. I can hardly walk, hobble around like a 90 year old, and am often in a lot of joint pain.
On the advice of the Breast Care Nurses, I stopped taking Letrozole just over 3 weeks ago and have an Oncologist appointment next week to try a different AI. I had been advised that I would start to feel better within 7-10 days but Iām still as sore as ever. How long did it take anyone else for the severe Letrozole side effects to stop? And was a different AI any better?
Hi
So sorry you were having such severe side effects with Letrozole. I have only taken it for four months and have joint aches, hot flushes (could be Herceptin aswell) and carpal tunnel in left hand only. I found walking and some exercise help with some joint pain. Iām definitely not as flexible as I was a year ago. I started with light weights and now I have chest wall pain.
I know of another lady who stopped Letrozole 2 months ago and still doesnāt feel any different. She was advised it can stay in your body for several months. She didnāt swap to another AI.
You may want to call the BCN nurses to talk through your own situation
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Thank you so much for your reply. Every day I hope that the side effects will reduce so itās helpful to know that for some people, it can take longer than the 7-10 days stated.
I stopped after 5 years on Ai last September. (Letrozole as the last one for 3 years)
Sorry to say that by Christmas, I no longer had insomnia or constipation and I could now climb the stairs with ease. I also realised that my hair was no longer falling out. My nails are getting stronger. I no longer have to run my hands under the cold tap in the morning to get them to unlock. Hot flushes gone.
Whether I still have the osteopenia, I doubt I will find out as I donāt suppose I will have a DEXA scan again
The only thing not to get better is the VA - thatās still with me and I suspect it always will be!
Thank you so much for your reply. Itās reassuring to know that it took a while for some of your Letrozole side effects to go away, and Iām sorry to hear about the continuing ones.
Iād say nearer 6 weeks - take it easy but try to get out and about - several (very) short walks rather than one long one.
I moved to Anastrozole - tried various brands and have found 2 that do not cause: itching, joint pain, muscle pain and only minimal edema.
Different brands really do have different effects
Wishing you all the best and a pain free, side effect free future
Thank you so much. I saw the Oncologist today and will take my first Anastrozole tomorrow. Which 2 brands have you found to cause the least side effects?
Hi Fran
Different women find different brands work best so its a bit of trial and error - I have found Aromax and Teva OK. Lasted a week on Accord but others find it is fine. Once you find what works insist on that brand - not always easy with the chronic shortages but persistence does succeed.
Good Luck
Thank you so much. I have been given Crescent brand and will keep a track of how I am on that. I am so very hopeful that the side effects may not be as debilitating as on Letrozoleā¦ā¦. Watch this space I guess. I wish you well
Thereās a great fb group called vaginal atrophy with lots of info about safe treatment . Thereās also a good video on breast cancer now YouTube channel where a pelvic floor physio is interviewed about treating side effects of hormone blockers on vagina / vulva .
Hi Fran
Just wondering if you found any solutions as this post was from last year and if you became free from joint pain after a certain time . I have terrible ankle pain and stiffness which stops me being active and I can relate to your phrase about ā hobbling around ā . Iām six weeks into stopping taking Letrozole and thinking I might be starting to notice a slight improvement . Iām also starting to visit a physio for support .
Dear @fran, I stopped Letrozole in October 2024 after 11months. The first thing to improve was my mood. I stopped being an angry, irritable monster! That took about a week. The next improvement was the dry vagina with its best buddies stress and urge incontinence. That improved gradually over 6 months and now I no longer need a vaginal moisturiser. My hair is improving after 8 months - thicker, starting to grow a little, but still dry. My finger nails are improving even more slowly but definately less ridged and brittle. What hasnt improved very much is the chronic insomnia so I have been treated by an NHS sleep clinic with a programme of CBTi which has been ongoing since December 2024 and just started to improve a tiny bit last week. I still have carpal tunnel syndrome in my right hand and bad back and hip pain but I started treatment with pre- existing back conditions. I still have high inflammation so have started to reduce meat consumption to one day a week. N.B. I stopped the treatment because it caused me to develop endometriosis and an ovarian cyst which are red flags for gynae cancer in a woman of my age (67).
I actually found that my joint pain was even worse on Anastrozole than on Letrozole . It got so excruciating that I couldnāt even go up or down stairs & I ended up having a steroid injection in one knee. I stopped Anastrozole after 8 months and with the support of my Oncologist, tried Exemestane which gave me a very severe rash & hives I then asked if I could tried the branded version - Aromasin - as a last resort. Amazingly, the joint pain has slowly started to reduce, and 5 months later, the pain is finally at a level which is manageable and Iām able to get out and about which feels wonderful. It seems that for some reason I have a severe inflammatory reaction, probably due to the fillers in the generic Aromatase Inhibitors, yet on the original version I am fine.
Thatās interesting that you talk about inflammation too - I wonder if you also react to the fillers in the generic versions, and whether it might be worth asking your Oncologist if you could try the branded version?
The branded versions are much more expensive so it seems that they donāt tend to get prescribed first, but it might be worth a try? I had very bad carpal tunnel syndrome when taking Letrozole, but now, although my hands & wrists tingle in the mornings, Iām no longer in pain from it.
I was taking Letrozole for 14 weeks and I just couldnāt take the joint pain anymore. I could barely walk or hold a cup. Iāve been told t9 come off it for 28days and theyāll try another AI. 12 days in I still feel awful. No improvement whatsoever. Will I ever be able to use my hands and legs properly again? Does it give you carpel tunnel and plantar fasciitis too? I canāt believe how awful this makes you feel. The operation and radiotherapy were a breeze in comparison!
I agree that for me, taking the AIs has been much harder than surgery (mastectomy & full lymph node clearance) and radiotherapy.
On Letrozole I suffered from carpal tunnel syndrome so badly that I had to wear wrist splints in bed, and do exercises with an online physio every single day.
That reduced when I changed to Anastrozole but I then suffered from plantar fasciitis which together with the extreme joint inflammation was so excruciatingly painful that I couldnāt go up & down stairs or even walk around the block and had to use a walking stick around the house. (Iāve been a power walker for over 20 years so this was horrendous).
It seems that this awful inflammation was caused by the fillers in the generic versions of the medication - since I have been on the original version of Exemestane (Aromasin), the plantar fasciitis has gone and the joint pain is manageable. My joints are still a bit stiff, and I still canāt walk āproperlyā by any means, but I am at a level that I can tolerate for the next 5 years . In my darkest days, I truly never believed that would happen. It has taken around 6 months to get to this stage of recovery.
Wishing you all the very best and I hope that the next medication you try is MUCH better for you.
Thank you so much Fran. I actually cried last night when I found the Letrozole side effects spoken about on here. I really thought the carpel tunnel and plantar fasciitis were another load of unrelated health issues. My GP actually told me that carpel wasnāt a documented side effect!! But the wome who are taking Letrozole clearly know better.
Iāll definitely bear in mind your comments about the future AI (and fillers). Youāve given me hope. Thanks again. Best of luck in your health journey and recovery.
Hi Fran, I hope you donāt mind me contacting you again.
Having had a challenging conversation today with the Breast care team, I can either stay on Letrozole (which was their preference as my side effects are not really much different from 4 weeks ago so, in their view, Letrozole isnāt causing my carpel tunnel or joint pain or plantar fasciitis now, even though I didnāt have any of those before taking it 4 months ago!) or I can take Exemestane. Thatās it. They donāt offer anything else. Iām trying to remain optimistic but Iām worried about increased joint pain etc.
Do you mind me asking which part of the country youāre in? I probably should go and see my GP but Iām not sure what they can do.
Of course I donāt mind you contacting me. Iām just sorry to hear that the pain is no better for you. Iām on the South Coast, in West Sussex.
For me, it was the Oncologist who decided which Aromatase Inhibitor I should be taking rather than a GP, and like your team, he hadnāt heard of the severe side effects that some of us can suffer. He was very amenable to me trying the original branded version after he saw the severe inflammation effects I had developed.
I wonder whether you could ask your Oncologist or Breast Care team to prescribe you the original branded version of Letrozole (itās called Femara) in case it might be the fillers in the generic versions that are causing this horrid inflammation?
It might be worth trying that first, in case it helps, and if not, then maybe try Exemestane? (But again, in your position I would ask for the branded, original version of that which is called Aromasin).
I REALLY hope it helps. Iāve just been for a short walk around the block which I hadnāt been able to do for 18 months, and although Iām slow and still hobble a bit, Iām no longer in pain which makes SUCH a difference. And the carpal tunnel syndrome and plantar fasciitis have totally disappeared.
.
. It got so excruciating that I couldnāt even go up or down stairs & I ended up having a steroid injection in one knee. I stopped Anastrozole after 8 months and with the support of my Oncologist, tried Exemestane which gave me a very severe rash & hives 
I then asked if I could tried the branded version - Aromasin - as a last resort. Amazingly, the joint pain has slowly started to reduce, and 5 months later, the pain is finally at a level which is manageable and Iām able to get out and about which feels wonderful. It seems that for some reason I have a severe inflammatory reaction, probably due to the fillers in the generic Aromatase Inhibitors, yet on the original version I am fine.