WASHINGTON — Federal authorities are considering making the anesthetic propofol — one of the drugs found in Michael Jackson’s home — a controlled substance, which would put new limits on its distribution.

The Drug Enforcement Administration was petitioned two years ago to make propofol a scheduled drug under the Controlled Substances Act. That designation is used to impose restrictions on distributing certain drugs prone to abuse and addiction.

A DEA spokesman confirmed Wednesday that the agency is considering adding propofol to the list of controlled substances. The brand-name version of propofol is called Diprivan. A nurse who provided nutritional therapy for Jackson has said he asked her for Diprivan to treat insomnia. Propofol is not recommended for such use and she said she refused the request.

Until Jackson’s death, the main concern about propofol was its potential for abuse by medical staff, because it is usually administered in hospitals to patients who need to be unconscious for surgery or other procedures.

The Food and Drug Administration has received an increasing number of reports about fatalities linked to propofol in recent years: 43 in 2008 and 35 in 2007, up from an average of 22 per year over the decade before that, according to FDA data. The increase may be due to increasing use of propofol over older barbiturates.

A central question in the Jackson investigation is who provided that drug and other prescription medications found at his rented Beverly Hills mansion. Investigators are talking to doctors who treated Jackson.

Investigators obtained a search warrant and removed several bottles of propofol from Jackon’s home, according to a person with knowledge of the investigation. The person is not authorized to speak publicly and requested anonymity.

Adding a drug to the federal list of controlled substances is a lengthy process. As part of its review, the DEA asks for a recommendation from officials at the Department of Health and Human Services. HHS experts can stop a drug from being added to the list if they recommend against doing so. Congress can also add specific drugs to the list through legislation.

The federal list of controlled substances is divided into five categories, ranging from some of the most potent, like heroin, to much milder products, like cough medicine with codeine.

Propofol is the country’s most widely used drug to induce general anesthesia, and also is used for other types of health provider-based sedation, said Dr. Stephen Parker, anesthesia chairman at Washington Hospital Center in the nation’s capital.

Hospitals and doctors’ offices must follow specific monitoring requirements for different levels of controlled substances, to track how much is bought and used, and who uses it.

Changing propofol to a controlled substance would require “accounting for every cc of the drug that was used,” Parker said, referring to the way the doses are measured. A teaspoon is about 5 cc’s.

“It would put up barriers for us to easily use the drug,” he said. “It’s a lot of bureaucracy and expense, frankly.”

For at least two years, the American Society of Anesthesiologists has had a committee looking into whether propofol should be made a controlled substance, but this has not been a high priority because abuse of propofol is “much, much less common” than of painkillers such as OxyContin, said Dr. David Zvara, anesthesia chairman at the University of North Carolina at Chapel Hill.

“It’s the drug you get when they say count back from 100 and you only make it to 97,” Zvara said. “It quickly and reliably puts people under — usually, very safely.”

At his university, it is used for about four out of every five procedures and is favored over older drugs like Pentothal and other barbiturates.

However, propofol depresses breathing and the heart rate and lowers blood pressure — risks that must be constantly monitored.

When it is abused, it’s usually by people seeking sleep, but even that is misguided, Zvara said.