Hi @JessC I am sorry that you are experiencing joint pain.
I take Femara (Letrozole) and so far I haven't experienced joint pain, though many women do. I had read that taking the Brand (in this case Femara) rather than a generic may assist with pain relief, as the fillers can be different. So far that's working for me.
Some people have had success with tart cherry capsules and even the antihistamine Claratine.
There is a Facebook group, Anastrozole(Arimidex)/Letrozole/Exemestane/ Hormone Therapy Support Group, and there is a lot of information there.
https://www.facebook.com/groups/384867198389816I hope those resources may help. xx