Which of the following is a common stimulant?

Amphetamines are a common class of stimulants widely recognized for their ability to increase alertness, attention, and energy levels. They function by enhancing the release of neurotransmitters such as dopamine and norepinephrine in the brain, which contribute to heightened levels of arousal and improved focus. This stimulant action makes amphetamines effective for treating conditions like ADHD (Attention Deficit Hyperactivity Disorder) and narcolepsy.

In contrast, Valium is a benzodiazepine, primarily used as an anxiolytic and sedative. Rohypnol is known for its sedative effects and is often associated with incapacitating individuals. Alcohol is classified as a depressant, which slows brain function and activity. Understanding these classifications helps clarify why amphetamines stand out as stimulants in this context.