In addition, Pep
was the name of a fictional product
Fenton Crackshell created a marketing campaign (with the help of another duck, who's name escapes me) extolling the virtues of pep on spec for Scrooge McDuck. Unfortunately, the ad campaign leaked to the public, creating a huge demand for Pep. Only one problem: No one knew what Pep was. So they took an experimental prototype of Gyro Gearloose's, a bubble gum whose bubbles cause the chewer to float, and named it Pep.
This caused problems, of course.