I was put on gabapentin for nerve pain 3weeks after my mastectomy. This coincided with me starting chemo so for the first week I felt terrible but the the chemo was rough each cycle after that anyway . So I don't know if there were side effects at the beginning apart from a dry mouth. Anyway, on gabepentin 600mg three times a day with no probs now for 5 months. I think they may have made my hot flushes less as I am not too bothered by them. But having one now of course! Lol. I have been advised to carry on until my radiation over and am happy to do so. No suicidal thoughts. Hope this helps. Angela