Ladybugs, cherished for their role in garden pest control, often raise questions about their potential toxicity to humans and household pets. These small, brightly colored insects are generally seen as beneficial. Concerns arise about what might happen if they are accidentally ingested. This article explores the actual risks associated with ladybugs.
Are Ladybugs Poisonous to Humans?
Native ladybugs are not considered poisonous to humans and pose no significant health threat if accidentally consumed. When disturbed or threatened, ladybugs may engage in “reflex bleeding,” releasing a yellowish or orange fluid from their leg joints. This fluid is harmless, though it has a foul odor and a bitter taste, serving as a deterrent to predators. In sensitive individuals, direct contact with this fluid or the insect itself might cause mild skin irritation. Ladybug poisoning in humans is exceptionally rare.
Are Ladybugs Poisonous to Pets?
While native ladybugs are largely harmless to pets, the Asian lady beetle (Harmonia axyridis) can cause issues if ingested, particularly by dogs. These beetles release defensive compounds containing alkaloids that can irritate the mouth and gastrointestinal tract. Ingesting a large quantity of Asian lady beetles can lead to symptoms such as excessive drooling, vomiting, diarrhea that may contain blood, reduced appetite, and lethargy. Documented cases show these beetles adhering to the roof of a dog’s mouth, causing painful ulcerations or chemical burns.
Distinguishing Ladybugs from Asian Lady Beetles
Differentiating between native ladybugs and Asian lady beetles is important, as the latter is the primary species of concern regarding pet toxicity. Native ladybugs typically have a vibrant red color with a consistent number of black spots and a black head with small white “cheeks.” Asian lady beetles, however, exhibit more variable coloration, ranging from light orange to bright red, and can have varying numbers of black spots or even no spots at all. A key identifying feature of the Asian lady beetle is a distinct “M” or “W” shaped black marking located behind its head on the white pronotum. Asian lady beetles also tend to congregate in large numbers, often seeking shelter indoors during cooler months, a behavior less common in native ladybugs.
What to Do After Accidental Ingestion
If a human accidentally ingests a ladybug or Asian lady beetle, rinsing the mouth with water is generally sufficient due to the bitter taste. For pets, particularly dogs, close observation is recommended if ingestion occurs. While mild cases may resolve on their own, symptoms such as persistent drooling, vomiting, or changes in behavior warrant veterinary attention. If a large number of beetles were consumed or if symptoms are severe or do not improve, contacting a veterinarian is advisable. In some instances, a veterinarian may need to manually remove beetles from the pet’s mouth, sometimes under sedation.