Neuropeptide S: The Brain Peptide That Reduces Fear Without Causing Drowsiness

This is a narrative review synthesizing findings from animal behavioral studies, electrophysiology experiments in amygdala circuits, receptor pharmacology, and human genetic association studies to characterize the NPS transmitter system.

Fear and anxiety disorders affect hundreds of millions of people, and current treatments often cause sedation. NPS is unusual because it reduces fear and anxiety while simultaneously promoting wakefulness — the opposite of benzodiazepines. This dual profile makes the NPS system a compelling target for developing anti-anxiety drugs that don't make patients drowsy.

Current anti-anxiety medications like benzodiazepines work but cause sedation, dependence, and cognitive impairment. The NPS system offers a fundamentally different approach — reducing fear while maintaining alertness. If NPS-based drugs can be developed, they could represent a new class of anxiolytics without the sedation trade-off that limits current treatments.

This is a review paper, not original research. Most findings about NPS anxiolytic effects come from animal models, and clinical translation to human anxiety disorders has not yet been demonstrated. The genetic associations with panic disorder are correlational.