Marketed as the original energy drink hence the "pep" in pepper and healthy for you to boot. The Doctor part implied it's health benefits and the punctuation was dropped from "Dr" for aesthetics. Research highlighted three points in the day when the human energy level drops. 10-2-4 were 10AM, 2PM and 4PM. the times of the day you were supposed to drink Dr Pepper to avoid the energy slump. The 10-2-4 has been replaced by a mysterious 23. This refers to the 23 flavors which combine to make the unique flavor of Dr Pepper.