Novacaine is also known as procaine which is in the ester family. The ester family is not used anymore for one thing, and one reason being is that too many people had an allergic reaction, of which can be fatal for some. Especially people today with their plethora of allergies and asthmatics. Just a tid-bit of info. Cocaine is an ester also, and is the original anesthetic and was also the original pain medication also before they knew their addictive properties.