Robert F. Kennedy’s “digital lover” says he maintained a secret drug habit despite his claims to have been “sober” for decades.

A forthcoming book alleges that Kennedy admitted as recently as last year to taking psychedelics like DMT, which is short for dimethyltryptamine, which produces a high that is often described as simulating a near-death experience.

Olivia Nuzzi made the revelation in her new tell-all memoir—details of which were shared with The New York Times in a feature that was published Friday.

Nuzzi, 32, wrote that the married Kennedy, 71, confided in her that he smokes DMT. She told him that she “liked uppers” and takes Adderall.

There is a stark difference between Adderall, which is prescribed to millions of Americans, and DMT, which the Drug Enforcement Agency says “has no approved medical use in the United States.”

Kennedy has been open about his struggles with drug addiction, which began after his father was assassinated. He used heroin as a teenager and into his late 20s, but says he kicked the habit in 1983—a year before his brother died of a drug overdose, and a decade before Nuzzi was born.

The Alcohol and Drug Foundation writes that DMT is “structurally similar” to magic mushrooms and is known to produce “short-acting and intense visual hallucinations.”

DMT does not lead to withdrawal symptoms that other drugs, like heroin, can cause.

Dimethyltryptamine is the psychoactive ingredient in the drug ayahuasca. Naturally occurring, it has been used ritually and medicinally in South American tribes for centuries. The DEA said it became a popular “drug of abuse” in the U.S. in the ’60s.

The Department of Health and Human Services, which Kennedy runs, did not return a request for comment. Kennedy denies having any interaction with Nuzzi beyond a magazine interview.