It's standard practise to give Tamoxifen for 5 years at the moment.However, there is research going on to possibly give it for 10 years.When you start this drug,can I suggest you take 1/4 of a tab for a few days then 1/2 a tab for a week and then go to full dose.That way your body gradually adjusts and there is less chance of pv spotting/discharge.My oncologist said it was good to start it this way.Along with hot flushes,it can also cause night waking and irritability.If these side effects don't settle down then there are other drugs that can help. Good luck with radiation-it's nowhere near as hard as chemo. Tonya xx