Insomnia is listed as a side effect of lipoic acid.

From my own experience I found I would get jittery too, on high doses daily.

I suspect if one gets insomnia and is sure it is the ALA, then perhaps you don't need it. There are reports to of stimulation of the heart as well.

We are all different and ALA does work for some people. But others have less impressive results and/or side effects.

Choosing supplements really needs an understanding of your cause. ALA is mostly suggested for people with diabetic neuropathy. But there are many other causes, which might not respond to ALA much.

You need to pay attention to what you were doing when this started. Medications/drugs from your doctor? A viral infection? trauma? excessive exercise? Reactions from foods? exposure to toxins and solvents in your daily activities? There are many more triggers. Is your PN constant or does it come and go? Things like that.