At very high concentrations, gabapentin can suppress the growth of cancer cells, presumably by affecting mitochondrial catabolism; however, the precise mechanism remains elusive. While it can be highly effective and even life-changing for some, gabapentin can also cause side effects, carry risks and is sometimes misused. Gabapentin can cause side effects that range from mild and short-lived to rare but serious. The most common ones affect the brain and nervous system. They include sleepiness, dizziness, unsteady walking, tiredness, swelling in the legs and feet, vision changes, tremor, and upset stomach. Gabapentin is used to help control partial seizures (convulsions) in the treatment of epilepsy. This medicine cannot cure epilepsy and will only work to control seizures for as long as you continue to take it. Overview: Gabapentin is used to treat certain people with seizures or nerve pain. Common side effects may include dizziness, sleepiness, or trouble with balance or coordination. Serious side. Gabapentin is approved to prevent and control partial seizures, relieve postherpetic neuralgia after shingles and moderate-to-severe restless legs syndrome. Learn what side effects to watch for, drugs to avoid while taking gabapentin, how to take gabapentin and other important questions and answers. Gabapentin is a prescription medicine used to treat nerve pain, seizures, restless legs syndrome, and other conditions. Learn about side effects, dosage, uses, warnings, interactions, and brand differences.