Neurontin Generic Name: gabapentin What is Neurontin (gabapentin)? Gabapentin affects chemicals and nerves in the body that are involved in the cause of seizures and some types of pain. The exact way that it works is unknown. You will find information on Neurontin at Consumer Information Professional Information Neurontin (gabapentin) capsules, tablets and oral solution are supplied as follows: 100 mg capsules; 300 mg capsules; 400 mg capsules; 600 mg tablets; 800 mg tablets; 250 mg/5 mL oral solution. Images of these preparations are available on this page. Additional Resources: Seizures