I have been on gabapentin and at the level the doctors wanted me at I was drunk ! or feeling like it, major headaches little weight gain.
Doctor put me on lyrica and not even to the level the doctor wanted me at started to have the same side effects, plus fast weight gain and could not feel to urineate.
Doctor pulled me off that and after one day off , I think I was in the bath room every hour or so and lost the 6 pounds fast.
For me all water weight.