The symptoms of jet lag—fatigue, headache, indigestion—are all too common. PostTV producer (and former flight attendant) Gillian Brockell explains what happens in your brain when you get jet-lagged and what scientists have discovered to fight it. (Gillian Brockell,Jhaan Elker/The Washington Post)

It’s 9 a.m. Do you know where your hypothalamus is?

Katie Redford thought hers was somewhere over the Atlantic Ocean. Having returned from a trip to South Africa one day last month, she was still waiting for the part of the brain that regulates her internal clock to catch up, like a piece of delayed luggage.

“It’s somewhere between here and London,” she said from her office at EarthRights International, a K Street human rights law firm that regularly dispatches her to distant time zones. With a circadian rhythm askew by seven hours, she was hoping that serial mugs of coffee would keep her going until she hit “the wall,” the profound 3 o’clock nosedive that defines the first few days back from a trip abroad.

“I did three red-eye [flights] in seven days, so my body is like, ‘Whatever. Sleep when you can,’ ” Redford said. “But that’s not unusual around here. There’s always somebody just getting back from somewhere.”

She’s right. Washington, home to the State Department, the Pentagon, the World Bank and countless international aid and advocacy groups, has long been a world capital of jet lag. But with a record-setting 7 million international passengers coming and going at Dulles International Airport last year, there is a greater chance than ever that the person next to you at Starbucks is on a sleep cycle split between D.C. and Dhaka.

According to local physicians and travel agents, the time-zone hopping among frequent fliers has become more intense in recent years as global trade has boomed, foreign crises have multiplied and the economic downturn has pushed more trips onto smaller staffs.

“Maybe you used to get sent to Germany a few times a year, but now you’re tacking on Jakarta, too,” said Helene Emsellem, professor of neurology at George Washington University and director of the Center for Sleep and Wake Disorders in Chevy Chase. She is seeing more patients who have to travel more frequently, with less time to rest during trips, shorter breaks between them and a smaller chance of flying in the sleep-inducing comfort of business class.

“Washington travel schedules are mind-boggling,” Emsellem said. “They are sending people all over the world all of the time, and not always in the same direction.”

Neither evolution nor medicine has yet to catch up with humanity’s newfound ability to wake up on one side of the planet and go to sleep on the other. But the search goes on for time-zone treatments beyond sleep aids such as Lunesta or melatonin, or standing in the sun when you want your internal clock to think “morning.” The Food and Drug Administration has approved a drug for use by blind patients that helps them adjust their internal clocks without light cues. Researchers at Washington University in St. Louis have found a polypeptide that allows mice to adjust to a new “time zone” in half the usual time, raising hopes for an eventual jet lag pill.

“It’s still years away,” Emsellem said. Until then, the semi-adjusted sleepwalk among us.

For many, time-zone management is as much a part of Washington life as traffic. From a taxi near London Heathrow Airport, Redford was e-mailing other Montgomery County parents about lacrosse schedules, and within an hour of landing at Dulles, she was driving a car pool. At the World Bank and the State Department, specializing in Latin American countries is known among some staffers as the “mommy track” because the time shifts of north-south travel are relatively minor.

“In Washington, you know at a conference where they’ve all flown in from around the world that by 2 o’clock, half the people will be sound asleep,” said Joseph Macmanus, a veteran Foreign Service officer and current ambassador to the International Atomic Energy Agency in Vienna.

Macmanus is legendary among diplomats and journalists for never changing his watch from East Coast time during five years of travel with secretaries of state Condoleezza Rice and Hillary Rodham Clinton. In order to keep in better touch with State Department headquarters, he slept during the day and worked all night in one world capital after another. No matter the local time, Macmanus would eat and sleep on Foggy Bottom time.

“If it’s 8 p.m. in Washington and 9 a.m. in Beijing, that’s your window to sleep,” Macmanus said. “Get up at 7 in the evening, and Washington is just waking.”

Macmanus takes no drugs. And after years of time shifting, he has either dismantled or shattered his internal clock.

“When coming here from Europe, I really don’t feel any jet lag at all any more,” he said during a visit from Austria last month.

Most travelers, though, are in constant search of help. They trade techniques including Ambien and abstinence (from alcohol and caffeine), and in-flight fasting or eating everything on the tray. Some rest, others jog. There are the catnappers and those who hold their eyelids up until the sun goes down.

Like many veteran globe-trotters, Redford tries to preset her body clock by jumping into a new time zone before she even gets there. She pulled an all-nighter before leaving South Africa.

“By the time you get on the plane, you just conk out, and you have a head start on the time change,” she said.

At the World Bank, a trip abroad is about as common as a visit to the staff cafeteria. With a D.C. staff of just over 7,000, the bank processed about 20,000 visa requests for foreign travel in 2013. Even so, staff physician Richard Kennedy said he has found that his international workforce is less likely than American counterparts to rely on medications.

“This is a population that prefers to take nothing and just tough it out than take Ambien,” the New York-born Kennedy said. “I find that we Americans are more likely to say, ‘Give me something.’ ”

Sleepiness at meetings is one thing, but jet lag can also make the brain fuzzy at more serious moments. Janet Fleischman has been a long-haul regular for more than 25 years as a human rights activist and public health consultant. She remembers wandering a street in what was then Czechoslovakia, trying to clear her jet-lagged mind enough to read a secret document.

“I had this coded address book to meet these dissidents, but I was so fried I couldn’t decode it,” Fleischman said. Another time, she was taking a sunrise run in Zambia, one of her basic jet lag palliatives, when she looked back sleepily and saw she that was being chased by a baboon.

“Suddenly, I was very focused,” she said.

Of course, for workaholic Washingtonians, the brutality of a work trip is sometimes easier to bear than the struggle for work-life balance. P.J. Crowely traveled with secretaries of defense and state for years, even while coaching his kids’ soccer teams at home.

“The fact is, I sometimes felt more refreshed on these trips,” he said, “than I did on the normal routine.”