@ARichies
Being uncertain is part and parcel of it all.
Asking what brand everyone found works for each of us may not help you - we are all different - my preferred brand is Sandoz
My advice, like others, is please give it a go! Menopause may also play a part - just take it one month at a time and not concentrate on the length of time - there's the option for your Oncologist to change to a different AI if Tamoxifen is not suiting you!
Here's a link to help you if you haven't seen it already, links within this link
Hormone therapy | Breast Cancer Network Australia (bcna.org.au)Take care and best wishes