On call. I am 47 years old and I've always been healthy. My main problem is insomnia. Sleeping pills don't work well, and they make me feel groggy. Finally, my doctor gave me a prescription for Desyrel, and he seems to have hit the bull's-eye. I've been sleeping much better and haven't noticed any side effects. But my pharmacist warned me about abnormal erections. Is it a serious concern?