Algae toxicity in pets

Algae toxicity — particularly from harmful blue-green algae (cyanobacteria) — poses a serious threat to pets, especially dogs. These toxic blooms often appear in warm, stagnant water bodies like ponds, lakes or slow-moving rivers.

Pets may be exposed by drinking the water, licking their fur after swimming, or even just wading through contaminated areas. Symptoms of algae toxicity can appear within minutes to hours and include vomiting, diarrhea, drooling, weakness, seizures, difficulty breathing and in severe cases, death. Quick veterinary intervention is critical, as some toxins can cause liver failure or neurotoxicity. To prevent exposure, keep pets away from water that appears discolored, has surface scum, or emits a foul odor — especially during hot weather. Always provide fresh drinking water and avoid letting pets swim in unfamiliar or stagnant bodies of water.

If exposure is suspected, rinse your pet immediately with clean water and seek emergency veterinary care. There is no specific antidote for most algae toxins, so treatment focuses on supportive care to manage symptoms and reduce toxin absorption.

Check the official website for the Oregon Health Authority, which publishes advisories for harmful algae blooms. If you come across questionable waterways, heed their message: when in doubt, stay out. Being vigilant and knowing the signs of toxicity can save your pet’s life.

---

In partnership with Willamette Veterinary Hospital

& Ark Animal Hospital

Tess Guy, DVM Ark Animal Hospital