The drink is called "Coca-Cola" because of the coca leaf and kola fruits that were used to add flavor. Dr. Pemberton's partner and bookkeeper, Frank Robinson, suggested the name "Coca-Cola" because he thought using the letter C twice would look better than if they used a K in the word "Cola". He then wrote down the name to use as a logo that is now very famous. The recipe was altered after a short while, after the cocaine/coca leaf reportedly caused cases of hallucinations. Coca has not been used in the formula since 1903.