How Does Provigil Help In Treating Nerve Damage?

Hello I just asked this question dont know where the answer would be posted so I figured I was ask here...My husband has Trigeminal Neuralgia/Neuropathy= his trigeminal nerves damaged not compressed. I ve seen question Does Provigil cause Trigeminal Neuralgia? He has had Trigeminal Neuralgia for 14 years said to be caused from being struck by lightening. Recently he has started taking Provigil to treat Adult ADD to find it actually HELPS his Trigeminal Neuralgia. Its like night and day difference taking Provigil. So my question is how is it that Provigil would help with nerve damage? Do note he does not take anti-seizure or pain meds as they do nothing to help. Only other med taken is Paxil.