Letrozole - side effects

Hi, when I went  through the menopause I had terrible symptoms and a GP who told me it was a 'natural process all women have to go through' and would not prescribe me any HRT so I just took herbal supplements which did help 

After a lumpectomy for left breast cancer in July 20223 I have been prescribed Letrozole which is giving me the same side effects which are - hot flushes followed by immediate headache, night sweats disturbed sleep, nightmares, migraines, mood changes, weight gain, and a constant swooshing in my left ear which is really weird!

My cancer was found in a routine mammogram at Stage 2 and there were no cancer cells in my lymph nodes (2 were removed) further testing showed I didn't need chemotherapy and there is a 13% chance of recurrence, I am to have 5 sessions of Radiotherapy staring this week, From what I have read the medication can give up to 50% reduction of the cancer recurring so its not guaranteed to stop it returning  (Ii am also taking the tables for the bone density and that seems to be ok) 

Taking all that into consideration my question are:

Do I really need to take this medication? 

Will the side effects subside or get worse?

Can I take herbal medication with it to combat the side effects?

If I need to take it is there an alternative I can try? 

I really dont want to go through all the menopause symptoms for the next 10 years! 

Thank you for your advice 

  • Hi SueJam,

    Thanks for getting in touch and welcome to our online community.

    My name is Carole and I’m one of the Cancer Information Nurse Specialists on the Macmillan Support Line.

    It’s understandable to have questions about treatment.

    When doctors offer or recommend treatment after surgery for breast cancer it’s to try to prevent recurrence. They use national guidelines, which are based on the results of clinical trials. NICE (National Institute for Health and Care Excellence) have this guidance on endocrine (hormone) therapy which might help to explain why your doctor prescribed letrozole for you.

    Offer an aromatase inhibitor as the initial adjuvant endocrine therapy for postmenopausal women with ER-positive invasive breast cancer who are at medium or high risk of disease recurrence. Offer tamoxifen to women who are at low risk of disease recurrence, or if aromatase inhibitors are not tolerated or are contraindicated.

    Letrozole, like all medication can cause side effects.

    It’s important to report any side effects to your GP or treatment team. This includes common side effects such as menopausal symptoms as well as ones which are not listed here, like swooshing in the ear.

    We’d recommend that you get in touch with them as soon as you can.

    For many people, side effects improve within the first few months of starting treatment.

    Unfortunately, for some people, side effects can be more difficult to manage.

    It can be trial and error to begin with, but usually doctors can recommend medication or tips which can help. Herbal remedies are not usually recommended as they can interact with medicines. Breast Cancer Now have produced this booklet which may be helpful to look at, before discussing further with your team.

    I hope this is helpful. If you have further questions, please don’t hesitate to get back in touch.

    Sending best wishes,


    You can also speak with the Macmillan Support Line team of experts. Phone free on 0808 808 0000 (7 days a week, 8am-8pm) or send us an email

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