Caffeine

Caffeine is a bitter alkaloid C8H10N4O2, which is used medicinally as a stimulant and diuretic.

The longer coffee gets into contact with water, the more caffeine could be extracted.

Thus, dripping coffee probably produces more caffeine than hot shot espresso. So next time if you need some stimulant, it's more effective to get a daily brew rather than a cappucino.