The FDA has approved Vanda Pharmaceuticals' Nereus (tradipitant) for the acute prevention of motion-induced vomiting in adults. This approval represents the first new pharmacologic treatment for motion sickness in more than 40 years. The drug acts as a potent and selective NK-1 receptor antagonist that directly addresses the release of substance P in the central nervous system caused by sensory conflict between visual, vestibular and proprioceptive inputs. Each year, tens of millions of people seek pharmacological treatment for motion sickness, often with over-the-counter options or prescribed medications. In placebo-controlled clinical trials, adverse effects were drowsiness (6% at 85 mg, 12% at 170 mg) and fatigue (6% at 85 mg, 8% at 170 mg) after a single dose. Nereus may interfere with the mental and physical abilities needed to drive or operate heavy machinery. This effect may be amplified with concomitant use of central nervous system depressant drugs or strong CYP3A4 inhibitors, so patients should be cautioned against activities requiring full mental attention.