The Lantana camara species, frequently chosen for its colorful, long-lasting flowers, is a popular ornamental shrub in many climates. Despite its widespread use, the plant contains compounds that are toxic to both humans and animals. All parts of the plant, especially the berries, pose a health risk if ingested. Understanding the specific chemical mechanism and resulting symptoms is important for safely managing this common garden plant.
The Chemical Basis of Lantana Toxicity
The toxicity of Lantana camara is primarily attributed to pentacyclic triterpenoids. These chemical structures act as hepatotoxins, specifically damaging liver cells. The two most significant toxins in this group are Lantadene A and Lantadene B. These compounds are not distributed evenly throughout the plant, but are found in the highest concentrations within the leaves and the unripe green berries, which present the greatest danger. The toxic mechanism is the same across all color variations of Lantana camara.
Specific Effects of Ingestion on Humans
Human exposure to Lantana camara often involves small children attracted to the plant’s berries. Ingestion typically leads to acute gastrointestinal distress, beginning with nausea, vomiting, and abdominal pain. Diarrhea and weakness may follow these initial symptoms. While most cases result in mild digestive upset, severe systemic toxicity is possible if a large quantity of unripe green berries is consumed, potentially leading to liver damage. Contact with the foliage may also trigger mild contact dermatitis in sensitive individuals.
Specific Effects of Ingestion on Animals and Pets
Lantana poisoning is a common veterinary issue, affecting both household pets and grazing livestock. The effects of ingestion vary depending on the animal species and the amount consumed. For dogs and cats, primary symptoms are acute and centered on the digestive system. Pets that consume the leaves or berries typically experience severe vomiting, hemorrhagic diarrhea, and lethargy. In severe poisonings, the pentacyclic triterpenoids can cause liver damage, manifesting as jaundice (yellowing of the eyes or gums), which can lead to organ failure if not treated promptly.
The impact on livestock, such as cattle, sheep, and goats, is often more severe. Grazing animals frequently consume large quantities of the leaves, which can induce poisoning when intake exceeds approximately one percent of the animal’s body weight. The lantadenes cause hepatotoxicity by disrupting the liver’s ability to excrete bile, leading to intrahepatic cholestasis. This liver dysfunction results in a buildup of phylloerythrin, a breakdown product of chlorophyll. When phylloerythrin enters the bloodstream, it reacts to sunlight, causing photosensitization, which leads to painful blistering and irritation on unpigmented skin areas.
Emergency Protocol and Prevention Strategies
Anyone suspecting ingestion of Lantana camara should immediately contact a poison control center or a veterinarian for pets. Professionals need to know which part of the plant was eaten and the estimated quantity to determine the appropriate course of action. Do not attempt to induce vomiting or give the individual or animal anything to eat or drink unless specifically instructed by a medical professional.
The best long-term strategy for prevention is to remove the plants from any area accessible to young children or household pets. When removing the shrub, gardeners should wear protective gloves to avoid contact dermatitis. Manual removal of the entire root system is the most effective method for eradication, as the plant will regrow if the stump is left behind. If complete removal is not possible, plant sterile varieties that do not produce berries or place the plants in areas safely out of reach.