What is a common side effect of sedatives and tranquilizers?

Drowsiness or sedation is a hallmark side effect of sedatives and tranquilizers. These medications are designed to depress the central nervous system, leading to a calming effect that often manifests as sleepiness or reduced alertness. This is particularly beneficial in treating anxiety, insomnia, or muscle spasms, enabling patients to relax or sleep better.

It's important to recognize that the primary action of sedatives and tranquilizers involves enhancing the effects of neurotransmitters like gamma-aminobutyric acid (GABA), which contributes to feelings of calm and relaxation. While the other options may be side effects associated with different classes of medications, they are not typically seen with sedatives and tranquilizers. For example, increased energy would be counterintuitive to the purpose of these drugs, while rapid heart rate may be more related to stimulants or other classes of medications, and dry mouth can be a side effect of various drugs, but it is not as characteristic of sedatives.