There is no period after "Dr" in Dr Pepper.

Explanation: From Snopes: "The period went missing in 1950 when the company changed the font. When presented in this new style, the lower case 'r' consisted of a small slanted line with a dot at its upper right. Well and good, but when a period was trailed after that new-fangled 'r,' the period and the r's dot seemed to form a colon and alter the 'r' into an 'i.' With the period there, 'Dr. Pepper' looked like 'Di: Pepper.' The solution was to drop the period. The font has changed again since then, but the period remains AWOL."

[Source: A 12-pack I saw at Stop & Shop. See previous Numbers of the Day here.]