I was given this by my GP to help with nerve pain following a severe bout of shingles, and costochondritis. The GP said that it would also help with my insomnia, and it did. He said it was very effective and had even taken it himself. I continued to take it for 2 months, until one night I was awoken by head banging Tinnitus. I have suffered from Tinnitus for years, but this was another level. Unfortunately, I stopped taking it immediately and suffered the consequences, severe headaches, heightened sensitivity to light, sound and movement. I am a Menieres sufferer so this may have been why I felt these effects, but it took me about 3 months to get the drug out of my system.