In Peru, the ancient Incas are believed to have used the leaves of the coca plant as a local anaesthetic in addition to its stimulant properties. It was also used for slave payment and is thought to play a role in the subsequent destruction of Incas culture when Spaniards realized the effects of chewing the coca leaves and took advantage of it. Cocaine was first used as a local anesthetic in 1884. The search for a less toxic and less addictive substitute led to the development of the aminoester local anesthetics stovaine in 1903 and procaine in 1904. Since then, several synthetic local anesthetic drugs have been developed and put into clinical use, notably lidocaine in 1943, bupivacaine in 1957, and prilocaine in 1959.