Some dogs have died after swimming in freshwater lakes and ponds with blue-green algae. Don't let this happen to you.

Blue-green algae (Cyanobacteria), is most abundant during hot weather in mid- to late-summer months. It grows and colonizes to form “blooms” that give the water a blue-green appearance and it only takes a few mouthfuls of algae-contaminated water to poison your dog fatally. Exposure to high levels of HABs and their toxins can cause diarrhea, nausea or vomiting; skin, eye or throat irritation; and allergic reactions or breathing difficulties. All blooms should be considered toxic.

The DEC has a map called New York State Harmful Algal Bloom and can show you where HABs are active. The yellow points on the map are HABs reported within the last two weeks. HABs may still be present in other areas, so avoid discolored water or surface scums.

What You Can Do If You Suspect Cyanobacteria Poisoning by Dogs Naturally

  • If your dog has gone into toxic waters, remove him from the water and hose him off immediately, to prevent him from licking and swallowing any of the water.
  • You may choose to take him to the vet, or if your dog looks fine, but you’re not sure the water is unsafe, you can choose to observe your dog for symptoms.
  • If your dog has been swimming in questionable water and he’s not showing any immediate symptoms, try giving him Arsenicum album 30C or Nux vomica 30C as soon as you can.
  • If your dog is showing signs of poisoning, you can continue giving him Arsenicum album 30C every 10 to 15 minutes on the way to the vet or Carbolic acid if you can get it.
  • These remedies won’t replace the emergency veterinary care he’ll need, but they can help reduce symptoms, especially if it’s accompanied by anxiety, diarrhea, and weakness.

Keep a close eye on your pets!