Caterpillars are the larvae of moths and butterflies. Many caterpillars are hairy, but few are harmful. In Canada, common stinging caterpillars include larvae of the tiger, tussock, tent and gypsy moths. Worldwide there are other types that can cause toxic or allergic reactions.
Are they toxic? (includes caterpillars in Canada only): The stinging caterpillar has hairs or spines capable of penetrating the skin and causing a local reaction. Exposure can occur through direct contact with a live or dead caterpillar or from indirect contact (with loose hairs present in cocoons or carried on clothing or pets). Caterpillar hairs that are embedded or stuck in the eye, skin and mouth may be difficult to see, and may require a magnifying glass to visualize.
Eye: The hairs may become embedded in the eye. Discomfort, redness, and swelling are common. Potential injury to the cornea and deeper chambers of the eye.
Skin: May cause an immediate prickly sensation or discomfort. Area may become red, swollen and have small raised bumps or blisters.
Ingestion: The hairs may become embedded in the tongue or mouth causing irritation, swelling, difficulty swallowing and drooling. Swelling in the mouth may result in breathing difficulties. If swallowed, an upset stomach and diarrhea may develop.
What to do?
Eye: Rinse eyes with a gentle stream of lukewarm water for 5 minutes by any of the following methods:
How can I prevent exposure? Do not touch or handle caterpillars.
Need more information: Call the Poison Control Centre.