Trips abroad with the president can be grueling for staff and journalists alike. Long hours, with stops in multiple time zones, are often the norm.

So it is not surprising that a political entourage might turn to Ambien, a sedative widely used as a sleep aid.

Still, regulators and medical experts were taken aback by allegations that Dr. Ronny Jackson, personal physician to Presidents Barack Obama and Donald Trump, handed out the pills to White House staff and to reporters on such trips.

The practice may have been accepted, but it is also illegal.

“You could be prosecuted,” said Melvin Patterson, a spokesman for the Drug Enforcement Administration.

White House officials have said the accusations against Jackson are false.

Ambien has been used by tens of millions of Americans and is one of the most commonly prescribed medications. But it is also a controlled substance, and there are strict rules governing its distribution.

Providing Ambien to passengers on a plane would violate the Controlled Substances Act, Patterson said. Penalties include suspension or revocation of a doctor’s authorization from the DEA to provide these drugs.

Ambien is classified as a Schedule 4 drug by the DEA, a category that also includes Valium and other drugs that have a comparatively low potential for addiction. By contrast, cocaine and methamphetamine are Schedule 2; heroin is Schedule 1.

Prescribing any drug that is a controlled substance means adhering to a set of regulations.

The prescribing physician must register with the DEA. The doctor must examine the patient and determine that the patient needs the drug.

The prescribing physician can only prescribe a controlled substance to patients in the state where he or she is licensed. A doctor in New Jersey cannot write a prescription for a patient in New York.

In addition, many states now have prescription drug monitoring programs for controlled substances, said Dr. Richard J. Baron, president of the American Board of Internal Medicine. Some now include Ambien in these registries.

A doctor in such a state has to enter information into the registry that identifies a patient. The reason is to prevent patients from going from doctor to doctor, getting addictive pills from each.

It is unusual for a doctor to hand out drugs, Baron said. Most of the time, they prescribe drugs. And it is just not good medical practice to prescribe — let alone hand out — drugs like Ambien to people you do not know.

That includes, he said, prescribing drugs to a patient’s family member who is not one of the doctor’s patients.

“You are supposed to have a doctor-patient relationship when prescribing,” he said. “That’s the reason these drugs are not available over the counter.”

Dr. David Orentlicher, a doctor and a law professor the University of Nevada, Las Vegas, who has advised the American Medical Association, said it is unethical for doctors to fail to adhere to good medical practices.

Those who need Ambien on long trips, he said, should see their own doctors and get prescriptions before the trip begins.

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