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Blue-Green Algae Toxicity in Dogs

Blue-green algae toxicity is life-threatening.

Blue-green algae is an extremely toxic substance found in lakes and ponds sometimes during hot weather. It's actually bacteria, and when it's swallowed, it can quickly cause severe toxicity and death in dogs.

Blue-green algae is also toxic to humans, cows, horses, birds, wildlife, and cats that are exposed to it. Dogs are more commonly affected than other species.

Where and When Does Blue-Green Algae Grow?

Blue-green algae can grow in freshwater lakes and streams, salt water, and backyard ponds. It usually thrives in hot water when water temperatures are warm. It uses sunshine and phosphorus and nitrogen from fertilizer run-off or decaying fish and plants to thrive. When it does, it's called a "bloom."

What Does a Blue-Green Algae Bloom Look Like?

A blue-green algae bloom looks like oily, green or blue paint under the water and it can stick on surfaces in the water. Unfortunately, there is no way to look at algae and know if it is toxic blue-green algae. Some blue-green algae is not toxic, and other types of algae can also look similar.

How Do Dogs Become Affected by Blue-Green Algae?

Dogs often love to dive into ponds and lakes or drink out of scummy puddles and ponds. Unlike people, who usually won't climb into yucky-looking water, dogs don't mind doing so. They can swallow the blue-green algae while swimming or grabbing toys in the water, or they might lick it off their fur and skin after they get out.

Dogs can also ingest blue-green algae by drinking out of standing water puddles or ponds.

Signs of Blue-Green Algae Toxicity in Dogs

Signs of toxicity can appear within hours of a dog eating blue-green algae. Once ingested, many different types of toxins are released by blue-green algae, which can cause issues in the body. The two most common types of toxins in blue-green algae cause liver failure and neurologic toxicity. Signs are connected to those toxicities and can include:

  • Weakness
  • Vomiting and diarrhea, sometimes bloody or tarry
  • Pale, blue, or yellow gums, skin, or whites of the eyes
  • Seizures
  • Coma
  • Drooling
  • Tearing
  • Difficulty breathing
  • Paralysis
  • Difficulty breathing

Treatment of Blue-Green Algae Toxicity in Dogs

Treatment of blue-green algae toxicity in dogs is supportive. There is no specific antidote for the poisoning. Therefore, it's critical that treatment is begun as quickly as possible after exposure and treatment may include:

  • Inducing vomiting
  • Intravenous fluids
  • Oxygen therapy
  • Anti-seizure medications
  • Blood transfusions

Prevention of Blue-Green Algae Toxicity in Dogs

If a body of water looks like algae is floating in it, don't allow your dog to get into it. If your dog has already gotten in before you notice it, get him out immediately, wash him off with copious amounts of clean water, and contact your veterinarian right away.

Don't let your dog drink out of standing water. Keep him on a leash as much as possible, and bring plenty of fresh, clean, cool water for him to drink instead when you go out.

Additionally, check for any swimming advisories for the body of water you are visiting before you let your dog get in.

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