Final answer:
Cocaine is legitimately used as a local anesthetic in the medical field, despite its potential for abuse and addiction.
Step-by-step explanation:
The only legitimate medical use of cocaine is as a local anesthetic. Cocaine is a tropane alkaloid and stimulant drug obtained primarily from the leaves of the coca plant. As a medical substance, it is used as the salt cocaine hydrochloride. The local anesthetic properties of cocaine were discovered early on, and despite its potential for abuse and addictive properties, it is still used for certain medical procedures where its anesthetic and vasoconstrictive properties can be advantageous.