Danger: Common plant Dumb Cane (Dieffenbachia)

The cells of the Dieffenbachia plant contain needle-shaped calcium oxalate crystals called raphides. If a leaf is chewed, these crystals can cause a temporary burning sensation and erythema. In rare cases, edema of tissues exposed to the plant have been reported. Mastication and ingestion generally result in only mild symptoms. With both children and pets, contact with dieffenbachia (typically from chewing) can cause a host of unpleasant symptoms, including oral irritation, excessive drooling, and localized swelling.
However, these effects are rarely life-threatening. In most cases, symptoms are mild, and can be successfully treated with analgesic agents, antihistamines, or medical charcoal. Gastric evacuation or lavage is "seldom" indicated. Jennifer S. Boyle, MD, PharmD, and Christopher P Holstege, MD, note that, "In a large retrospective study of 188 patients with plant oxalate exposure, all cases were determined to be minor and all resolved with minor or no treatment." They also note that, "In patients with exposure to toxic plants, 70% are children younger than 5 years.

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