I had spinal fusion at L3-L4 in Dec. The doctor also removed Harrington rods that had been used in fusion at L4-S1 in 1983. Have been dealing with arthritis pain in low back since 2000. I have used Vicodin in small doses since then as needed until last summer when I needed it more regularly to manage pain from spondylolisthesis until surgery. In Aug 2013, I fell 9 feet on my back and head. That's when my primary dr prescribed Gralise, I've been taking 1200 mg daily since then. The fall caused a concussion, whiplash over upper back & neck. Symptoms were horrid (severe & constant headaches, noise sensitivity, irritability, memeory issues, communication issues etc) and I was not able to run my business for many months. I'm still not back to my function level before the fall. When I was in hospital after fusion, the pain was really severe, and I was not taking the Gralise for 4-5 days. The symptoms I've been having line up with Gabapentin negative effects and I have real trouble getting to sleep, usually I get 7-8 hours after I do get to sleep. I also have been having ongoing cognitive problems with memory and language. I thought most of the severe nerve pain and high pain levels were due to surgery but now I'm wondering how much the Gralise is a factor. Do you have any thoughts? I'd really like to function semi normally!