Yes, there is so much written about tamoxifen and some people do suffer quite bad side effects so it is scary when you start taking it. But I try to remind myself that it is also very effective at keeping hormone related BC away. While I don't like taking a drug everyday for 5 years, I'm kind of grateful that it's available. It makes me feel a bit safer, a bit less likely to get cancer again.I'm sure your radiotherapy will be still be effective even after a bit of a wait. I had a break of about two months between finishing chemo (not sure if you've had that) and starting radiotherapy. If you've had chemo, I think the break gives your body a chance to recover a little before they hit you with the next treatment. Although radiation is not nearly as bad as chemo.