By Kristina Fiore

An unusual and highly toxic compound is making headlines after President Trump reportedly supported it in a conversation in the Oval Office.

Trump voiced support for oleandrin, a botanical made from the poisonous oleander plant, during a July meeting attended by MyPillow.com founder and CEO Mike Lindell and Secretary of Housing and Urban Development Ben Carson, MD.

Lindell, a longtime Trump supporter who has a stake in the biotech that's developing oleandrin -- Phoenix Biotechnology -- said that Trump said "the FDA should be approving it."

FDA Commissioner Stephen Hahn, MD, has resisted any efforts around the compound, but Phoenix Biotechnology director Andrew Whitney has said if he can't get oleandrin to market as a drug, he'll push for it as a dietary supplement.

The thought of another potentially dangerous compound being touted as a "miracle cure" by the Trump administration, like hydroxychloroquine, had medical experts up in arms on Twitter on Monday.

"Oleandrin? Yeah that would definitely end up killing people," tweeted David Juurlink, MD, PhD, of Sunnybrook Health Sciences Center in Toronto.

Juurlink said that oleandrin is "akin to digoxin. Too much can cause nausea, vomiting and diarrhea, but the main concern is arrhythmias, which can be fatal."

Jennifer Gunter, MD, tweeted that it's "easier to kill a person with oleandrin than COVID-19" and highlighted a case report in which two people were poisoned after eating snails that had munched on an oleander plant.

What makes oleander -- the word generally covers the Nerium oleander, Nerium indicum, and Nerium odorum plants, and other common names are kaner, rosebay and rose laurel -- so deadly? All parts of it contain cardiac glycosides, the most potent being oleandrin and neriine, both of which are similar to the chief cardiac glycoside of foxglove, digoxin.

According to a 2010 case report and review, oleandrin directly interferes with the sodium-potassium pump of the heart, potentially leading to arrhythmias. Ingestion also causes gastrointestinal effects, and both appear about four hours after ingestion.

Authors of an earlier case report calculated that 4 grams of oleander leaves would be fatal.

Juurlink highlighted a case report in which a patient committed suicide using oleander leaves. That paper estimates toxic blood levels of oleandrin at 1 to 2 ng/ml and a fatal blood level of 9.8 to 10 ng/mL.

So far, there's no published evidence that oleandrin can help patients with COVID-19. A recent study tested the compound against SARS-CoV-2 in Vero cells, but no animal or human data are available for this indication. That study was a preprint in bioRxiv and one of its authors, Robert Newman, is the chairman of the Phoenix Biotechnology scientific advisory board.

Oleandrin has also been studied in vitro as a possible anti-cancer medication, but it's "unclear whether these effects can occur in the human body," according to a Memorial Sloan Kettering Cancer Center info page on oleandrin.

"No one should take oleandrin to prevent COVID," said Juurlink. "Anyone gullible and foolish enough to take it despite this advice should get their affairs in order beforehand."