The name "Dr. Pepper" was first used commercially in 1885. It was introduced nationally in the United States at the 1904 Louisiana Purchase Exposition as a new kind of soda pop, made with 23 flavours.

It was formulated by Brooklyn-born pharmacist Charles Alderton in Morrison's Old Corner Drug Store in Waco, Texas. To test his new drink, he first offered it to store owner Wade Morrison, who also found it to his liking. Patrons at Morrison's soda fountain soon learned of Alderton's new drink and began ordering a "Waco". Alderton gave the formula to Morrison, who named it Dr. Pepper (later stylized as "Dr Pepper").