an alkaloid obtained from the leaves of the coca shrub. It is an anodyne. Cocaine is used in the form of powders and solutions as a local anesthetic in ophthalmology, otolaryngology, urology, and stomatology. It is highly toxic. When first absorbed, it is a stimulant; it later inhibits the nervous system. Repeated, uncontrolled use of cocaine may result in addiction, or cocainism.