I found it took at least 12 months after surgery, chemo and radiation to get close to my old energy back, and this included my taking the oestrogen blocker Femara. I mentioned earlier that side effects I experienced were bone aches, deterioration in my bone density and my hair returned in a much thinner form. After three years on Femara I asked what other options there were and tried a different drug Arimidex. This suited me better for a while but at the 4.5 year mark I have gone off everything as the bone pain became debilitating. I am close to the end of the treatment cycle, which has allowed this – I feel calmer, less bone pain, am sleeping better and my hair seems to be thickening.
My suggestion is to try another brand,as mentioned in earlier post, keep an eye on your bone density.