Brief Answer:
it's the same drug

Detailed Answer:
Hello,

gabapentin is the active ingredient of neurontin, so it's the same drug!

Regarding its side effects (which I guess you've already experienced) there are a lot of them. Most patients experience only few of them or even none. Regarding the balance problem you've mentioned, this drug may indeed cause it. Actually there is no neurological symptom that this drug can't cause as a side effect. The most common neurological side effects are somnolence, dizziness, fatigue, ataxia and headache. Ataxia may be the cause of your balance problems.

I hope you find my comment helpful!
You can contact me again, if you'd like any clarification or further information (regarding the rest of its side effects for example). I haven't gone further into the side effects because they are far too many to mention them all here. If you'd like we can discuss about any other particular side effect that bothers you or go deeper into more side effects.

Kind Regards!

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