There is information about letrozole and side effects on the website of the UK charity Breast Cancer Now
It may subside, as your body adjusts. Take simple painkillers such as paracetamol to help. If your headaches get worse, or persistent, then do let your GP or hospital team know. They can assess you and advise further.
I hope this helps,
Please get back to us if you need any more information or support. You may find it helpful to talk things through with one of the nurses on our helpline. The number to call is Freephone 0808 800 4040 and the lines are open from 9am till 5pm Monday to Friday.
