Ask HN: Faster caffeine metabolism/flushing

I am a coffee fanatic who can't handle the caffeine any more because it takes too long for the caffeine to be flushed out of my system. If I take a cappuccino in the morning, I sometimes can't fall asleep at midnight. Or I fall asleep and wake up in the night.

I distinctly remember drinking up to three cups of coffee in bed and falling asleep shortly after. I think I started being hypersensitive to caffeine 3 years ago when I went crazy on coffee, taking multiple highly concentrated cups daily.

I'm starting to look into how I can metabolise the caffeine faster because coffee offers huge advantages to me. Makes me sharper mentally, and I'm able to focus more. I've read about sulforaphane (derived from broccoli, abundant in broccoli sprouts) and I'm currently experimenting with that.

Any ideas on how I could flush caffeine out of my system faster?