I looked this up online, so it could be inaccurate.. but apparently 12oz of DDP has 41mg of caffeine, and 12oz of coffee has 200mg of caffeine. So.. 20oz of coffee would have 333.33mg of caffeine. You'd have to drink about 96oz of DDP to be equal to 20oz of coffee.
My math might be slightly off. But that should help a little.
Awk! Thanks, Ashley - I don't think my system can hold that much
Just as well. Dunkin Donuts is on my way to work; I'd need to go out of my way to hit (not literally, I hope - but without caffeine I'm not making any promises!) Sonic.
I love that you are trying to figure out the right "dosage" of caffiene! Yesterday, I did not have coffee until noon. WTH was I thinking?!? I won't make that mistake again. No way!