What is a common effect of depressant drugs on the body?

Depressant drugs are known to slow down the central nervous system, which affects bodily functions such as heart rate. When depressants are consumed, they often lead to a decrease in heart rate as part of their calming effects. This overall reduction in physiological activity can contribute to feelings of relaxation and sedation, which are characteristic of depressant substances.

In contrast, the other options describe effects that are generally associated with stimulant drugs or heightened physiological states rather than depressants. For instance, an increase in energy levels and enhancement of sensory perception are typically correlated with stimulant use, which activates the central nervous system rather than suppressing it. Similarly, heightened reflex response suggests increased alertness and quick reaction times, which are not consistent with the calming and sedative effects produced by depressants. Thus, the decrease in heart rate aligns accurately with the common effects experienced when using depressant drugs.