Enlarge / Yellow oleander. (credit: Getty | FlowerPhotos)

Last September, a New Jersey toddler got ahold of a bottle of weight loss supplements. The product, purchased by the toddler’s mothers, was labeled as the dried root of tejocote, aka Mexican hawthorn, a large shrub-like plant found in Mexico and Latin America that produces crabapple-like fruits. Although there’s little data on the effects of the dried root—including any supporting its use for weight loss—tejocote is generally considered safe to consume.

But the toddler soon experienced nausea and vomiting. At an emergency department, doctors noted low heart rate, falling blood pressure, irregular heartbeats, and a telltale anomaly on an electrocardiogram.

The weight loss supplement was, in fact, not harmless tejocote root—it was entirely pieces of yellow oleander, a poisonous plant containing cardiac glycosides, including a toxic cardenolide, that can cause dysrhythmia and cardiac arrest, among other things.