My cat had gabapentin. It will sometimes make her sick though so I don't use it much. Plus she gets super drowsy. She can usually keep it down if I can time it just right with her food. I was given the gabapentin because of her arthritis.
I've found gabapentin and lyrica helpful for sciatica pain, personally. But it has side effects. It can cause GERD if taken longterm (personal experience) and it DEPLETES vitamins B6, B12, A, D, and K, folic acid, biotin, carnitine, calcium and
magnesium. Gabapentin acts on the GABA receptors in the brain so why not try GABA powder instead? You can easily order it in powder form online. I order it in bulk from amazon (bulk supplements) for my daughter to help with her anxiety. It's a very calming amino acid.