Letrozole Side Effects

My wife is in the 5 th month of letrozole as BC tumour reduction therapy and has been coping amazingly well with all the normal side effects but lately the joint pains have started to become almost intolerable. Unfortunately she also suffers from lupus which is also not great for joint pain. Have any of you wonderful ladies come across any medication or alternative therapy to help with the joint pain. She has a 3rd MRI coming up soon to check on tumour reduction and is hoping for wide area excision soon after. Help would really be appreciated by both of us. Alipalli, husband of Alibongo.

Hi Alipalli and welcome to the BCC forums

In addition to the support and replies you will soon have here, please feel free to call our helpliners to talk through your queries, lines are open 9-5 weekdays and 10-2 Saturdays on 0808 800 6000

You and your wife may find the following link to more support service ideas from BCC useful:


Take care


I am very sorry to hear that your wife is having problems with Letrozole. I have been on it for 4 years and I too are having problems with it with regards to aches and pains and am seeking a way of reducing the discomfort. I am presently on Ibruprofen, which long term might not be an option. Ibruprofen is not good on the stomach so I take Omeprazole to help.
I am sure that you will get many replies to your post


I am about to start letrozole this week so am interested to read about possible SE. My hospital offer acupuncture which can help with certain SE. Its worth asking your onc. I hope that they find something to help.
Kind regards,

Hi Allipalli,
Sorry your wife is getting alot of joint pains, I got those when starting with letrozole but when I was given calcium and vitamin D tablets the joints eased alot. (Anecdotal I know but the pains came back if I stopped them and went after I restarted) If nothing else works might be worth asking for blood test to check calcium & vit d levels.
Hope all goes well in the future

Hi Allipalli.
I started on Letrozole last August. I developed joint pain after about a month. Initially vitamin D supplements helped but I developed problems with both hips. X-rays showed high levels of inflammation which meant I had trouble walking upstairs. My oncologist changed my meds to exemestane (Aromasin) in January and I have only had minor aches since. It might be worth asking your oncologist if this could be an option for your wife. I have continued with cod liver oil and glucosamine supplements and also a general vitamin and mineral supplement which has ginseng to help with fatigue often found with these meds. This seems to be helping a lot . Best wishes to you both - hope the scan goes well. Buffy3 - I have acupuncture every fortnight to help with the flushes and general wellbeing and it really works. I sleep so well after a session. Love to all x

1 Like

Afternoon All,
I’ve been taking Letrozole for nearly 2 months after taking Tamoxifen since last July, I electced to have my ovaries removed in Jan which made me post menopausal, hence change to Letrozole in March (I’m 46)
The hot flushed seem to be worse with Letrozole, hopefully they will settle down as they weren’t so bad with Tamoxifen. But the joint ache is much worse, does it get better or worse the longer we take the drug, I was hoping my body would get used to it. I am exercising more and doing Pilates (in an attempt to shed those chemo pounds) but am still hobbling around after sitting too long and 1st thing in the morning. My sympathies to your wife Alipalli.
Love to all.

1 Like

I had been on Letrozole for about 2 years when I decided to take a break from work which lasted 2 years!! Up till then the only thing that I had noticed with regards to aches and pains was that I was getting stiffer and stiffer as time went on but when I started a new job as a homehelp for a charity, completely different from any of my previous jobs, and where I was doing things like hoovering etc for at least a couple of hours a day I started to get real problems. At the moment I am off sick, I have just had a scan which was clear, I ache a lot, cannot move very far and on painkillers to help. I have decided that I will have to change jobs as it is obvious that a physical job isn’t ideal although I have only one more year of Letrozole and that will be 5yrs Tamoxifen and 5 years Letrozole.
I think that a combination of the job and Letrozole have brought about my current problems although my Onc admitted that 1 in 3 patients are severely affected by aching joints etc whilst on Letrozole.
What I have done today is to buy some cod liver oil and glucosamine as it seems to have helped people so looking forward to seeing some improvement.
When I got my scan results on Wednesday I was so relieved and I am so glad that I had the Tamoxifen and Letrozole even though at times it has been unpleasant.

Thanks for all your responses Ladies, I’ll pass them to my wife twins evening. The vitamin D thing sounds interesting’ I know she’s taking calcium supplements and glucosamine and she goes to The Haven regularly where she has acupuncture which I know she finds helpful. Hazelmary that’s great news and I am sure my wife will take fpgreat comfort from the knowledge that the pain is worth it in the long run, she does know that but I guess you all understand the emotional issues, the ups, the downs, far better than I do, but then I don’t have to understand, I just have to try and help. Thanks to you all for resounding. Alipalli.

1 Like

Hi Everyone, I have been on Letrozole since end of October and apart from sore joints first thing in the morning I have been fine. I have been taking Cod Liver Oil, Glucosamine and Omega 3 every day to help with the sore fingers etc. and this seemed to help BUT the last 3 weeks I have had really bad back pain. Today I phoned my breastcare nurse in despair as I was in agony and painkillers were not really helping much. She spoke to my surgeon who said I have to come off of the Letrozole for a couple of weeks to see if that is the cause and if it is then I will get a change of tablet. and if it is just the same I will have to have a scan to check out the cause of the pain. The pain is in my lower back and worse on the left side, has anyone else experienced this? I keep fearing the worse and hope it is not bone mets, as I had the all clear on my yearly mammo last month. I’ll keep you posted as to how this test goes but there is absolutely no way I continue with Letrozole for another 4.5 years if it is the cause, apart from anything else I would find it impossible to keep working. K M

Hello K M
I started on"Letrozole 4 years ago after 5 years of Tamoxifen and your symptons are practically the same as mine are now.
When I first started on Letrozole I was okay apart from the Burning Mouth Syndrome that started 6 months into the drug. My husband had been made redundant and I was still at work fulltime in an office and he took over the housework etc so I wasn’t really doing much physical work as such.
He then took early retirement as he was 55 and I decided to take a break from work as I was getting tired and stressed in the job and he then got a pt job gardening so I stayed at home for 2 years. so apart from normal household things was okay. I was getting stiff at times and got the old muscle spasm but not too bad.
I then, and this is when it all happened, got a homehelp job with a charity working 15 hrs a week, housework, shopping etc and thats when it all started. Just doing the extra physical work along with the drug brought me a load of aches and pains, mainly in my back, hips etc.
My Onc sent me for a MRI scan which was clear and he at last said one was the main SEs with Letrozole is the aches and pains and is severe in 1 of 3 patients.
I am now on Ibruprofen, Omeprazole to counteract the stomach problems caused by Ibruprofen and a muscle relaxant and thats where we are. I have been signed off sick for 4 weeks and am now deciding whether to give up my job and find something less physical but I will probably wait until I have finished Letrozole next year.
The scan did show a change in bone marrow but that is expected in the length of time I have been on Letrozole.
I think that there are SEs with all AIs but there are others to chose from. I have been offered a change but as I have only a year to go I will try and manage.
Hope you get an answer soon.

1 Like

I have been given letrozole this week and its been ok but it is making me feel depressed anyone else had this effect from this drug?

Have now been off the tablets for a total of 5 TABLETS and have absolutely no back pain at all, so I am obviously convinced that it was caused by these tablets. It will be interesting to see what my surgeon puts me on to in 2 weeks time.
Hazelmary - thanks for your reply - asked GP about those tablets and she said they were for “acid” and gave me something else, problem is wants me to take them every night and quite frankly I don’t need them on a daily basis.
Assisi - sorry to hear you are feeling a bit down - is that the only side effect you are experiencing?
KM x

Kitten I take one a day so far so good my mood has now passed and I am feeling much better thanks just going out to have my hair done on this lovely morning it makes you feel better going to the hairdresser don’t you think keep up the good work girls you are all doing so well Hugs to you all

Kitten-mad - if you are taking ibuprofen or any anti inflammatory on a regular basis the omeprazole ( or something similar) works to prevent problems and you do need to take them every day not just when you feel you need them - the last thing you want is a big stomach problem on top of everything else. If you’ve stopped all ibuprofen and any other anti inflammatories then I’d speak to your GP about stopping them

Assisi - great that your mood has lifted. A visit to the hairdresser is a must but I need to see if I can cope with the hair wash in the salon. I’m also planning a manicure and a pedicure, but one thing at a time.
kitten mad - great you have no more discomfort. I am still stiff and sore, feeling generally under the weather physically most of the time. Family say I am doing loads more so that is reassuring. And the latest scan showed the Letrozole has reduced the breast tumour. So worth it, definitely.
Elinda - I was on Omaprozole but that was when I was taking 8 Paracetemols a day. I asked my GP about dosage and she thought 6 Paracetemols would be better. So I cut down and only take on a need-to basis, usually 2 a day mid morning to cover the most active time of day for me. I stopped the Omaprozole and seem to be fine.
Thanks for your helpful comments, Hazel Mary. I understand, like you, that there are other AI’s available which is very encouraging.

Susan I am back from the hairdressers and feel much better just had my lunch regarding the hair washing my hairdresser has a back wash so that’s not so bad I only have to sit and tilt my head backwards then the girl blows it for me its amazing what a treat can do to perk you up all the best to you all xxx

I had a lumpectomy in late November, I have one more cycle of FEC 75 for adjuvant IDC, ER+ HER2+ no lymph node involvement. I am starting rads in about 6 weeks and probably hormone therapy at about the same time. But am v undecided what HR therapy regieme go for - Tamoxifen or Letrozole?

I have been reading this thread about the bad side effects that some of you are getting on Letrozole - 'unbearable muscle/joint pain etc. Sounds like a nightmare! this has really put me off going on it, even though my ONC has recommended it.
I have been offered Letrozole or Tamoxifen and am trying to decide which would be the best option For me. There is also the risk of Osteoporosis and Hair thinning on Letrozole, which I must admit has put me off it still further! With Tamoxifen, possible SE’s are weight gain and hair loss and god knows what else! Having gone through the cold cap - so far with some success having kept most of my hair during chemo - the thought of 5 years of hormone replacement therapy, still with the potential ongoing apprehenson of hair loss really depresses me! Of course I know everyone is different and SE’s may not apply in my case, so apologies for sounding a bit of a wimp! I’m one day post FEC 5 and generally feeling a bit low. :frowning:
I am going to talk through my concerns about SE’s with my ONC, but just wondered if anyone who is a bit further down the line than I am could perhaps offer any thoughts or advice? Perhaps what your experiences were? Thanks So much. X

I stopped Letrozole after nearly 4 months. I could not take the SE of the deep joint pain and well, I felt just plain all around God awful. I had no node involvement, DCIS with two small tumors of IDC microinvasion. Had a 2nd onc consult on should I stay or should I go and both gave their blessing. Here are a couple of articles on Breastcancer.org the American site that you may find of interest:
Femara Better Than Tamoxifen for Certain Types of Breast Cancer
About 25% of Women Either Don’t Start or Don’t Finish Hormonal Therapy
Gentle hugs Mejane and you have my full support in whatever you decide.
LB, x

I have been on letrozole since September of last year. I have had very little joint pain, sometimes feeling a bit stiff when I have been resting too long and feel the same on waking. Once I am moving about it usually eases.
I have no hair thinning, no weight gain or loss. I already have osteopaenia and to have be monitored closely, for any developments towards osteoporosis.
My understanding is most women have no problems with this drug. In any event, most drugs have side effects, if you were to read throughly what might happen whilst taking Ibrufen, you would no doubt leave it on the supermarket shelf!
Please don’t worry too much that it will be horrendous for you. Discuss it with your onc for reassurance.