FDA's Aug. 14 response letter to a new dietary ingredient (NDI) notification said the company had already tested oleandrin as a potential prescription drug and could not at the same time seek permission to sell it as a supplement. The letter also stated that the notification does not provide an adequate basis to conclude that a dietary supplement containing the ingredient, “Oleandrin,” when used under the recommended conditions will reasonably be expected to be safe. Last month, AHPA strongly discouraged sales or marketing of dietary supplements that contain any part of the oleander plant (Nerium oleander) or its constituent, oleandrin. Oleandrin is a cardiac glycoside found in the oleander plant. Oleander is a highly toxic plant, and death has been associated with oral ingestion of even small amounts of oleander leaf.

The extract comes from the Nerium oleander plant; the raw oleander plant is highly toxic and consuming it can be fatal. There are no peer-reviewed, published studies on the impact of oleandrin on Covid-19, and there's no public evidence it has been studied in patients with Covid-19.