Oleander Is a Poisonous Plant, Not a Cure for COVID-19

The evergreen shrub (also known as Nerium indicum, Nerium odorum plants, and other names like kaner, rosebay and rose laurel) is part of the Apocynaceae or dogbane family and it contains a gummy, clear sap. Native to northern Africa and the eastern Mediterranean, the hearty plant can be found in hot, coastal areas of the United States, like Florida.

The dark green foliage is complemented by funnel-shaped flowers that bloom in clusters and come in shades like white, pink, red or yellow. While the eye-catching plants can grow to between 6 and 12 feet (1.8 to 3.6 meters) and are coveted by gardeners for their tolerance of different soil types and climates, experts are clear that all parts of the plant are poisonous to humans and animals and have been responsible for cases of accidental poisoning around the world.

"Oleander is a plant that has been used in herbal medicine since the 15th century," says holistic nurse practitioner and host of the Feminist Wellness Podcast, Victoria Albina, NP, MPH. "While it has been used for many purposes from hangover to cancer treatment to an antiviral, oleander must be used under the care of an extremely experienced clinical herbalist or other clinician as it is a dangerous plant that must be used with the utmost care, and is not one I use or would use in my clinical practice."

Oleander has been researched for its potential applications in cancer treatment and as an antiviral agent by pharmaceutical drug-development company Phoenix Biotechnologies (the same one pushing it as a cure for COVID-19). Some of the studies have shown successful results in the lab, but it has not been tested in humans.

Oleander also is where the derivative botanical oleandrin comes from. It's very similar to digoxin, the compound derived from foxglove plants. It's used to treat very advanced heart failure patients. "Oleandrin is a toxic compound, a toxic cardiac glycoside, found in the oleander plant," Albina explains.

Cardiac glycosides are found in several plants, like the digitalis (foxglove), and the compounds are used in medications that treat heart failure and certain irregular heartbeats. However, people who ingest plants containing cardiac glycosides or who take medications containing cardiac glycosides every day can easily overdose.

"What's important to note about [oleandrin] is that it has actually been shown to reduce life expectancy (although its effects might improve quality of life for patients with advanced heart failure)," says Ryan Marino, M.D., a board certified emergency medicine physician in Cleveland, Ohio, and an expert in medical toxicology. "There is no indication that such cardioactive steroids, like digoxin and oleandrin, would help with viral infections like COVID-19."

There is absolutely no published evidence that oleander can offer any benefit for people with COVID-19, and experts are worried that by publicizing the plant's name in relation to the pandemic may lead people to erroneously self-medicate.

"There is one single preprint study, with significant conflicts of interest from the people who are trying to sell oleandrin, that claims there is a benefit in COVID-19-infected monkey kidney cells, which has not passed the peer review process that is standard for scientific literature," Marino says. "Oleander has no approved therapeutic indications."

A 2010 case report and review found that oleandrin specifically interferes with the sodium-potassium pump of the heart, which can potentially lead to arrhythmias (problem with the rate or rhythm of the heartbeat). Consuming oleander can also cause gastrointestinal effects.

"I think there are many potential dangers when we use an extract from a poisonous plant on a mass scale, and as a nurse practitioner and herbalist with a master's in public health, the roll out of an oleander-based drug — especially one that has been moved quickly through the FDA's approval process — is worrisome to say the least," Albina says.

"Every part of the oleander plant is toxic," Marino says. "These plants have long been used as hedgerows because they can kill any life that tries to eat them. People living in areas with these plants are taught not to even use the sticks as skewers for cooking food because of the risk of toxicity.

"If oleandrin were to be used in humans, the window before it became toxic — and poisoned people — would be so small as to be almost impossible to achieve safely. Like drinking from a fire hose, there is a very high amount of guaranteed risk associated with minimal potential for benefit."

Marino says he's deeply concerned by the false reporting on the benefits of oleander and everyone should exercise extreme caution and critical thought when considering any medical advice and to seek out evidence-based information in the form of hard science.

"We are in the middle of a devastating pandemic that has killed over 170,000 Americans," he says. We have also seen the rise of anti-scientific sentiment and science denialism ... Science does not inherently favor one political side over another, and while science may be uncertain at times — especially when facing a novel virus causing a global pandemic — it is not something that can be framed as having two sides. Science simply is. Anyone who says otherwise is trying to manipulate or take advantage."