Gabapentin is an anticonvulsant medication that helps manage seizures due to epilepsy. It's also taken for nerve pain, which different conditions, including diabetes and shingles, can cause. It works effectively and helps to block the pain signal in the brain. clumsiness, unsteadiness, dizziness, drowsiness, and sleepiness are the common side effects of gabapentin. Heart Attack is the harsh side effect of Gabapentin.