Quite interested by this topic.
There's definitely some kick in Red Bull or Monster.
If I'm out, Red Bull is my go-to drink as I do feel it helps make my balance better. I wonder if its as it says on the tin it just makes you more alert.
I used to find that a couple of beers helped my balance but put that down to knowing that as I'd had one or two that I knew I needed to concentrate more.
Unrelated comment - I sometimes think that if I didn't know I had AMN that I would be less aware and as a result have better balance. If I have a stumble it triggers memories if previous stumbles/falls and that seems to put me off balance a bit longer.
Anyway. Red Bull makes a marked improvement to me.
Let us know how your Husband is getting on Diane.