Neurontin is an anticonvulsant with the generic name gabapentin. It is prescribed to treat partial seizures, restless legs syndrome, hot flashes, and nerve pain. Neurontin is taken orally in tablet, capsule, or liquid form. Common side effects may include headache, dizziness, fatigue, fever, vomiting, and problems with balance or eye movements. Other serious side effects may include weak breathing, blue-colored lips, fingers, toes, or skin, increased seizures, aggressive behavior, sexual dysfunction, and suicidal thoughts.