Hi, You are using tamoxifen tablet that means you are pre-menopausal and are on treatment for hormone positive breast cancer. Now, estrogen block can lead to many post menopausal symptoms like hot flushes as you are experiencing. I should know the frequency of hot flush and how does it restrict your normal activities. Anyway Your doc has prescribed Efexor XL (venlafexin) which is a standard medication in your case. But other medications are also there like gabapentin. Your best option may be to modify your life style first. Do not take too much of alcohol, caffeine. Habit of smoking to quit. use cloth of cotton. You may use cotton cloth soaked with water and tie it over neck. these measures on long term may be beneficial. Consult your oncologist. Take care.