In my personal experience,about 15 years ago,I was on
Neurontin ( GABA )
for 4 years. It was prescribed to me
for pain along with an opioid. It worked nicely. I am unaware of Neurontin being prescribed for sleep.
There is one caution: although every person is different, I found this medication extremely difficult to withdrawal from,even tapering. If you have concerns speak with your Dr.