I make some Tennessee bourbon essence, hell I like the flavour of this one, and added about 1 ml per liter of Parisian essence (caramel 150c) to darken it up a bit.
I hit it last night, not hugely excessive but enough to feel it, and I'll be damned if I could get to sleep. It was 5.30 the last time I checked the clock. Didn't rise again until lunchtime. Luckily I have an understanding wife who is used to my nuances of nightshift (when I'm on it which I'm not).
Lying in bed with that same buzz coffee gives you is a nuisance. You know that one where you're tired and want to sleep but your brain just wont shut down whizzing around at a million miles per hour.
Can't say for sure it was the Parisian essence but I'm damned if I can figure out what else it could be. Everything else last night was completely normal.
I'll be returning those two bottles I have left to the carbon filter next neutral run.