Elephant ear is a common name used to describe several species of large-leaved plants, primarily those within the Araceae family, including the genera Colocasia, Alocasia, and Caladium. Despite their popularity as ornamental plants, all parts of these plants contain substances that are toxic if ingested or handled improperly. These plants are poisonous and must be handled with caution, especially around children and pets.
The Specific Toxin and How It Works
The mechanism of toxicity in elephant ear plants is primarily physical, caused by microscopic, needle-shaped structures called raphides. These raphides are crystals composed of insoluble calcium oxalate. They are tightly packed within specialized cells throughout the plant’s leaves, stems, and roots.
When any part of the plant is chewed or broken, the stored calcium oxalate crystals are expelled. These sharp needles penetrate the delicate tissues of the mouth, throat, and gastrointestinal tract. This immediate physical penetration triggers a localized inflammatory response, causing intense pain and irritation. The toxicity is not purely chemical but results from an immediate, painful mechanical injury.
Signs and Symptoms of Exposure
Exposure to the plant’s sap or tissues causes immediate symptoms in both humans and animals due to the painful crystal penetration. For humans, the most common first reaction is an intense burning sensation in the mouth and throat. This is quickly followed by localized swelling of the tongue, lips, and oral cavity, which can be severe enough to make speaking or swallowing difficult.
Other symptoms of ingestion include excessive salivation, a hoarse voice, and sometimes blistering. If a large amount is consumed, a person may also experience gastrointestinal upset such as nausea, vomiting, or diarrhea. Serious complications are uncommon, though swelling that restricts the airway is a rare possibility.
Pets show similar signs of immediate oral distress after biting or chewing the plant. The most obvious symptom is excessive drooling or foaming at the mouth, as the animal attempts to clear the irritant. Animals may also paw at their face, display signs of oral pain, and refuse to eat due to discomfort.
Pets may also exhibit vomiting, difficulty swallowing, or a decreased appetite. The sharp irritation from the crystals usually discourages an animal from consuming enough of the plant to cause a severe systemic reaction. Any noticeable reaction requires prompt attention to alleviate the pet’s discomfort.
Emergency Response and Prevention
Immediate action is necessary following any known or suspected exposure. For ingestion, the affected person or pet should immediately rinse the mouth to remove any remaining plant material or sap. Rinsing the mouth with cold water or milk can help soothe the burning sensation and wash away the irritating crystals.
Do not attempt to induce vomiting unless specifically instructed by a medical professional. If the sap has contacted the skin or eyes, the area should be thoroughly rinsed with water. A person experiencing severe swelling, especially if it affects breathing, should be taken to an emergency room immediately.
For human exposure, the national Poison Help hotline (1-800-222-1222) can provide expert guidance. Pet owners should contact a veterinarian or a dedicated Pet Poison Helpline for professional advice. To prevent exposure, gardeners should wear gloves when handling the plants to avoid skin irritation. All parts of the plant, including discarded cuttings, should be disposed of safely, and household plants should be kept out of reach of children and pets.