Jet lag and sleep phase disorders

Case history

A 30-year-old business executive presents with difficulty falling asleep on business trips. He makes 3-4 trips to China from New York every month. His typical non-stop New York-Beijing flight leaves New York at 5 p.m. and reaches Beijing at 8 p.m. (local time) the next day. He complains of difficulty falling asleep at night, feeling sleepy the next morning, and often dozing off through business negotiations. On arriving back in New York 3-4 days later, he feels extremely fatigued, and has headaches, muscle soreness, and constipation, which self-resolve in a few days. He is otherwise healthy, he does not take any medications, and his physical examination is normal.