Short answer: Asian lady beetles can be harmful to dogs if a dog ingests them, especially in larger quantities, but problems are relatively uncommon and usually involve irritation or chemical burns in the mouth, GI upset, or rare more serious reactions. Details

• What makes them risky
  • When threatened, Asian lady beetles secrete a defensive fluid that is irritating and potentially caustic to mucous membranes and the gastrointestinal tract if swallowed in sufficient quantities. This can cause mouth ulcers, drooling, vomiting, diarrhea, or anorexia in some cases. In very rare instances, severe exposure has been reported.

• How dogs are typically affected
  • Most dogs will avoid or quickly spit out the beetles due to the unpalatable taste and strong odor, so incidents usually involve multiple beetles or existing mouth/gut sensitivities. Ingesting a few beetles may cause mild irritation; larger ingestions raise the risk of more pronounced GI symptoms or oral ulcers.

• What to do if a dog encounters them
  • If a dog has eaten or may have ingested beetles, monitor for signs such as drooling, pawing at the mouth, vomiting, or diarrhea. Rinse the mouth with water if feasible, offer fresh water, and contact a veterinarian for guidance, especially if many beetles were ingested or if signs worsen.

• Notable cautions
  • Large infestations or repeated exposure are more concerning, and there is a small chance of more serious reactions. While rare, some cases have required veterinary care, and a few reports describe significant mouth or GI involvement.

Practical guidance

• Prevention: try to reduce beetle exposure in areas where dogs spend time, especially during peak beetle seasons. Seal entry points and gently remove beetles from indoor spaces to minimize risk.

• First aid steps at home: if you know a dog has ingested beetles, offer water, observe for mouth irritation or GI signs, and seek veterinary advice if symptoms persist or if a large number were ingested. Do not induce vomiting unless a veterinarian instructs you to do so.

If you’d like, I can tailor guidance to your location and provide a quick checklist for recognizing symptoms and when to seek urgent care.