Which of the following is classified under CNS depressants?

Xanax, which is the correct answer, is classified as a central nervous system (CNS) depressant. It belongs to a class of medications known as benzodiazepines, which are commonly prescribed for anxiety and panic disorders. These medications work by enhancing the effect of a neurotransmitter called gamma-aminobutyric acid (GABA) in the brain, leading to a calming effect and reduced neuronal activity. This makes them effective for managing anxiety and promoting sleep but also carries the risk of sedation, drowsiness, and respiratory depression, particularly when combined with other CNS depressants.

In contrast, the other medications listed—Adderall, Ritalin, and Focalin—are classified as CNS stimulants. These drugs are primarily prescribed for attention deficit hyperactivity disorder (ADHD) and work by increasing levels of dopamine and norepinephrine in the brain, which helps improve focus, attention, and impulse control. Since these medications stimulate brain activity rather than depress it, they do not fall under the classification of CNS depressants.