Hi @Pommy8, I just started on Letrozole after having bad side effects on tamoxifen. I was ok on tamoxifen for just over a year when really terrible side effects saw me back at tge oncologist and ultimately stopping them for 6 wks.
It's now my 4 week on Letrozole. I notice a couple things after 4 days but so far I am ok. I am a little stiff in the morning but a couple of stretches and my morning walk seems to set up my day well.
Don't be frightened. Give it a go and just monitor yourself. If things do get hard for you talk to your oncologist and they can change things. But remember that it really only affects about a 1/3 of those that take it so fingers crossed that won't be you.