Gabapentin 100 mg is used to treat epilepsy and is taken for nerve pain, it stops seizures by reducing the abnormal electrical activity in the brain. It helps to increase reduce pain and get calmness. It works in the brain through the GABA. treats back pain, Postherpetic Neuralgia, Epilepsy, Chronic Pain, and Seizures and belongs to the drug class gamma-aminobutyric acid analogs. It treats chronic pain and also helps to reduce anxiety and stress. That is why some people buy Gabapentin 100 mg for anxiety.