Which of the following drugs is classified as a stimulant?

Cocaine is classified as a stimulant because it primarily increases activity in the central nervous system (CNS). This effect leads to heightened alertness, increased energy, and a sense of euphoria, which are characteristic responses associated with stimulant substances. The mechanism by which cocaine operates involves the inhibition of dopamine reuptake, resulting in heightened levels of this neurotransmitter in the brain, which affects mood and pleasure sensations.

In contrast, heroin is an opioid that acts as a depressant, slowing down CNS activity and producing sedation and euphoria. Alcohol is also classified as a depressant, affecting motor control and producing relaxation followed by impairment. LSD, or lysergic acid diethylamide, is a hallucinogen that alters perceptions, moods, and cognitive processes rather than stimulating the CNS. This differentiation among the categories of drugs is crucial for understanding their effects and implications for both individual health and broader legal concerns related to substance use.