The introduced cane toad, Rhinella marina (formerly known as Bufo marinus) can cause poisoning in dogs. Dog owners need to be aware of this danger. The cane toad was introduced in Queensland and is now well established throughout northern Australia, including Northern Territory, northern New South Wales, and northern Western Australia. Occasional findings in Victoria, South Australia and Tasmania may have been stowaways in shipments of furniture of people moving interstate. The range of cane toads in Australia is expanding.

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Native toads in Australia are not known to be poisonous. Only the introduced cane toad is poisonous. Both tadpoles and adult cane toads can cause poisoning.

Cane toads produce a mixture of toxins collectively called bufotoxin. Bufotoxin is found in the skin of tadpoles and adult cane toads. Bufotoxin is secreted from glands on the head, called parotid glands. The secretion is a thick, milky liquid and the toad produces more of it when threatened. Poisoning occurs when a dog licks or mouths a cane toad, or picks a cane toad up in its mouth. Bufotoxin is rapidly absorbed through the oral membranes.

Clinical signs of cane toad poisoning are almost immediate. They include:

• Abundant salivation.
• Pawing at the mouth.
• Shaking the head.
• Whimpering or yelping.
• Retching or vomiting.
• Brick-red color inside the mouth.
• The dog may appear disoriented, blind and unable to walk normally.
• The dog may have difficulty breathing.
• In severe poisoning, the dog may have seizures.

Bufotoxin is an irritant to the mouth and has toxic effects on the heart and on the nervous system. Toxic effects include irregular heartbeat, abnormal heart rate (may be abnormally slow or abnormally fast) and elevated blood pressure. Effects on the nervous system include abnormal eye movements, seizures, and coma. Sometimes dogs will adopt a position resembling tetanus with the back arched backward and the legs extended.

The dog’s mouth should be immediately flushed with copious running water, unless the dog is having seizures or is unconscious. ℹ️Veterinary attention should be sought without delay. It is not necessary to capture the toad to show to your veterinarian, because there is only one toxic species of toad in Australia. If there is any risk that the dog has swallowed the toad, swallowed toad tadpoles or eaten any part of the skin of a toad, the veterinarian must be advised of this.

Veterinary treatment may include:

• Monitoring of the heart rate.
• Appropriate cardiac drugs to normalize the heart rate and regularity.
• Fluid therapy to correct imbalances in potassium and sodium in the blood.
• Appropriate medications to control seizures.

⚠️Cane toad poisoning is a veterinary emergency. Mortality in untreated cases ranges from 20% to 100%. Prognosis depends on the amount of secretion absorbed, and on timeliness and aggressiveness of treatment. In animals given prompt treatment, there is usually marked improvement within 12-24 hours.

Generally, it is not possible to confirm that a sudden death was due to toad poisoning. Occasionally if a dog ate tadpoles or part of a toad, remnants may be found in the stomach, but most dogs that are poisoned have only licked or mouthed a toad.

The owner must be vigilant to ensure that the dog does not lick or mouth cane toads. It is wise to teach the dog using positive reinforcement techniques, to turn away from something and look back to the owner for a treat, such as the “Leave it” cue.

Cats are less commonly poisoned by cane toads, compared to dogs. Cane toad poisoning may occur in children who handle a cane toad or tadpoles and then fail to wash their hands before eating food. People with cuts or abrasions on their hands should not handle cane toads or cane toad tadpoles.