pain
"I took Neurontin (Gabapentin) for three months as a treatment for chronic pain following a herniated lumbar disc a year and a half ago.  Anti-inflammatories and other medicines such as Oxycodone, Tramadol, etc. had minimal effect.

After increasing my dosage over the course of three weeks, Neurontin completely eliminated the pain.  However, I gained weight rapidly (nearly 20 pounds in 2 months), retained a tremendous amount of water, to the point where my jewelry wouldn't fit and my shoes were very tight, and the constipation was awful and even laxatives didn't help.  Also, I was fatigued all the time.  Unfortunately, the side effects were just too much for me.  I still haven't found a good replacement medicine for the pain.  All the side effects!"