Side Effects. Drowsiness, dizziness, loss of coordination, tiredness, blurred/double vision, unusual eye movements, or shaking (tremor) may occur. Side Effects. Dizziness may occur. If this effect persists or worsens, tell your doctor or pharmacist promptly. This medication may make you sleepy during the day. Learn about Neurontin (Gabapentin) may treat, uses, dosage, side effects, drug interactions, warnings, patient labeling, reviews, and related medications. Neurontin (gabapentin) is used to treat seizures and nerve pain caused by the herpes virus. Includes Neurontin side effects, interactions and indications. 14 Common Side effects of Januvia (Sitagliptin) Every medicine has its own side effect. Medicines are beneficial as well as they can be problem to the patient if the side effects are serious. For the Consumer. Applies to gabapentin: oral capsule, oral solution, oral suspension, oral tablet. Along with its needed effects, gabapentin (the active ingredient contained in Neurontin) may cause some unwanted effects. Pictures of Neurontin (Gabapentin), drug imprint information, side effects for the patient. Here are the Most Common Docusate Sodium (Colace) Side Effects for Long Term, Short Term and also read Serious Side Effects of of Colace Docusate Sodium Including Types of mg. At first the Neuorntin made me a bit drowsy, but after my body adjusted the side effects went away. My MD also treats me with accupuncture. I am not keen on taking too many meds, but I do find that the Neurontin does take the pain away.