Bad Bugs, Bad Bugs: What You Should Do to Keep Your Pets Safe

August 1, 2018

a kitten hiding behind a plant

Our pets are curious by nature, and it’s one of the things we love most about them. But every so often, this unending curiosity can get them into trouble when they unknowingly encounter potentially dangerous substances—or creatures. As summer continues in full swing, your pet may be spending more time outdoors, and this could lead to encounters of the bug kinds. But how do you know which bugs are friendly visitors, and which are “bad bugs,” for your pets? 

The ASPCA Animal Poison Control Center (APCC) has all the facts, and we want you to know which insects’ defense mechanisms could lead to problems should your pet get too close. 


While they may look cool and fuzzy, it is best to keep dogs and cats away from caterpillars. The hairs found on many caterpillars can be harmful when they are either touched or ingested. While contact with skin is unlikely in pets due to their fur coats, our four-legged friends may try to ingest caterpillars.   While ingestion is not life threatening to pets, caterpillars can cause such issues as head shaking, pawing at the mouth, vomiting, diarrhea and irritation to the lips, mouth and throat.  

Asian ladybeetle

Asian ladybeetle, or Harmonia axyridis, is an insect many people are familiar with due to their tendency to infiltrate homes during the winter months. When ingested by dogs and cats, Asian ladybeetles secrete defensive compounds that may cause irritation and even ulceration in the mouth. While one or two of these small bugs are not likely to be a big deal, some pets don’t know when to stop, and more serious problems like stomach ulcers may be seen when a large number of beetles are ingested.

Walking sticks

Unlike Asian ladybeetles who make their presences known every fall, walking sticks are harder to find due to their tendency to blend in with their backgrounds. For some species, blending in isn’t the only defense mechanism, and they can also secrete either a foul-smelling compound or a compound that is irritating to the eyes or mouth. Interacting or ingesting a walking stick could lead to drooling, shaking, pawing at the mouth or eyes, or vomiting. 


Whether you call them fireflies, lightening bugs or “blinkies,” the one thing that remains the same is that fireflies are toxic to another type of four-legged friend—lizards. Fireflies contain lucibufagins, a toxin that affects the stomach and heart. Unfortunately for pet lizards, particularly bearded dragons who may be less selective in what they eat, ingesting fireflies can be a deadly mistake. The onset of symptoms is fast after ingestion—15 minutes to 2 hours—and may include head shaking, opening their mouths wide or vomiting. Eventually, symptoms could increase in severity and include difficulty breathing, color change and death.  

If you suspect your pet has been exposed to any poisonous substances or ingested something dangerous, contact your veterinarian or call Animal Poison Control Center (APCC) at 888-426-4435 immediately.