National Certified Addiction Counselor, Level I (NCAC I) Practice Exam 2026 – Comprehensive All-in-One Guide to Exam Success!

Among the choices provided, alcohol is not classified as a stimulant. Instead, it is categorized as a depressant. Alcohol primarily affects the central nervous system by slowing down brain activity, leading to a decrease in alertness and cognitive function, which contrasts sharply with the effects of stimulant substances.

In contrast, caffeine is a well-known stimulant that increases alertness and energy levels by blocking adenosine receptors in the brain. Nicotine, found in tobacco products, is also a stimulant that can enhance mood, focus, and cognitive function. Amphetamines, another type of stimulant, are known for their capacity to increase energy and concentration by boosting the levels of certain neurotransmitters, such as dopamine and norepinephrine, in the brain.

Understanding these classifications is vital for recognizing how different substances affect the body and behavior, especially within the context of addiction counseling, where knowledge of the pharmacological effects of various drugs is essential.