This is incredibly interesting - amply demonstrating how personal and individual people's experiences are to a particular drug. Almost like glasses, what works for one person can be not just useless but an antithesis.
I was started out, like many, on phenytoin and whilst it sort of did a job, on the strong dosage I started on I could definitely feel 'Mikd Cognitive Impairment'. Whereas before I could run a day long workshop on the technical aspects of video production, three weeks of phenytoin gave me issues making loose change. I also had an issue with memory and impulse control.
Switching to Keppra was such a wonderful experience, getting back all my 'Executive Function', memory and self regulation ability. Within a couple of weeks I could foresee getting back to work.
Now, keppra - for me - did make one feel a bit like 'a couple of beers at lunchtime' physically. Not mentally, just a little uncoordinated. I know others get far worse. But the feeling subsides in a few days to a week or so.
And I will take the high Executive Function every time. I am, to all intents and purposes, back to my normal self. Just as I would hope for anyone here when they find their own 'Goldilocks' AED too. Good to know the broader range of choices as well as hear both good and bad on what's out there.