I had practically no reaction to the Arimidex for about a year & a half. All of a sudden it really kicked in: deformed fingers & toes, challenging joint pain and muscle pain & spasms. The worst is I thought I was beginning into dementia. Had an appointment to be evaluated by neuropsychologist when I inadvertently found that the “dementia” I’ve been experiencing are side effects of the Arimidex. What a relief! I’ll only be miserable for few more years😜. I wish I had known this was a possibility. It would have saved me a great deal of angst. I understand About 50 percent of patients experience these effects within the first 2 years. I will continue with Arimidex as long as necessary and not take myself too seriously 😊. I hope you’re in the other 50 per cent ❤️