I have been taking Ultram 50mg 3 times daily for almost 8 years. I had severe back pain that extended down my left leg. I went to a Neurologist and he performed back surgery. I did quite well for about 3 months and then was experiencing the same problems. He then prescribed Ultram ER and it has worked great. The only side affects I have recognized have been sleeplessness, hot flashes, nausea that goes away in about 1 hour after taking it, and super energy. The benefits far outway the side affects. My 34 year old brother was prescribed the 50 mg. tablets and he had to be transported to the emergency room because of a seizure. Needless to say he was advised not to ever take another pill.