I don’t think there is any doubt that some people are affected more severely by Letrozole than others - like chemo reactions, it’s hard to work out what are the triggers and ‘cures’. I agree that fillers can cause some reactions but many people have tried several brands only to find that, after a temporary alleviation, the old problems recur. I’m on femara with no aches or pain but switched to arimidex for three months to see if it helped vaginal dryness (it didn’t) but I did not have any new or different side effects. It’s frustrating and depressing for those who are struggling on for a benefit they believe in but can’t quantify or guarantee. Strength to you all.