@TaraV I’ve been on Letrozole nearly 3 years. It was rough to start with for 3 or so months but I found walking an hour daily helped a lot with aches and pains - I could walk thru it I guess.
There are about 8 different manufacturers of Letrozole in Australia who use different fillings and coatings.There has been a bit of talk online about sensitivity to different fillers and coatings. I didn’t pay much heed initially but last year found I had a reaction to the brand supplied here by Chemist King causing me spiralling down into depression after 3 months. I now take Sandoz brand from Chemist Warehouse and much better - been on it 12 months.
I’m not advocating any particular brand but am suggesting maybe a change of brand and see if it makes a difference like it did for me. I now believe not all Letrozole tablets are the same even though the active ingredient is.