Hi Rainbowlight2007- welcome to the forum.
I just was looking at some info on Neurontin the other day-
some info and links-
below a section from - http://web.tampabay.rr.com/lymecfs/nfaq.htm
It is important, since Neurontin is excreted through the kidneys, that your creatinine level is normal. This is a routine blood level that would have been drawn along with your usual yearly blood work. Neurontin is not metabolized by the liver.
Many users have found that hydration is vitally important while using this drug. A small amount of water retention is normal, especially when ramping up (increasing) doses. If you find that your rings are tight and/or your toes are swollen, AND you are drinking less than four quarts (approximately four liters) of water a day, you may find that increasing your intake of water will help eliminate any excess fluid unless your doctor has placed you on a water restriction. However, if you gain over 5-10 pounds, you may temporarily need an occasional diuretic to help flush out the excess water.
If you find that you are continuing to have worsening water retention, your doctor needs to be consulted as soon as possible to insure your kidney and cardiac functions are normal.
Over the years, the need for obtaining gabapentin levels have become less important.
After about two weeks on round-the-clock doses, Neurontin is totally excreted from the body within 8-9 hours (if there are no kidney problems).
If one is not on round-the-clock doses, Neurontin is totally excreted from the body in approximately 4 hours.
For optimal dosing, Neurontin should be divided into a four (or more) times a day frequency to keep a constant blood level. If one is taking Neurontin on a three (or less) times a day and is experiencing break-through pain, the easiest experiment (with the doctor's permission) would be to divide the daily dose into four equal doses to see if that solves the problem. ]
and a list of info sites -