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Blue-Ringed Octopus Bite

Blue-Ringed Octopus Bite Facts

  • The blue-ringed octopus, a cephalopod, is less than 8 inches in diameter with its tentacles extended. It has blue rings and luminous tentacles. It is found in the Indo-Pacific Ocean area (Australia, New Zealand, New Guinea and Japan). The blue-ringed octopus is not an aggressive marine animal.
  • Cephalopods, a name used to refer to all octopi, usually live in rocky ocean bottoms. The blue-ringed octopus lives in rock pools, under shells and in shallow waters making then a risk to people wading in tide pools, children, and divers alike. They are rarely seen in water deeper than 10 feet.
  • When at rest, the octopus has dark brown to yellow bands over the body with superimposed blue patches or rings. When excited or angered, the body darkens and the blue circles or stripes glow iridescent blue.
  • The blue-ringed octopus does not release inky fluid like other octopi are able to do.
  • When human contact with a blue-ringed octopus occurs, it is usually accidental. Avoid handling this octopus because its sting contains tetrodotoxin, which paralyzes the victim (similar to pufferfish poisoning). The sting is often fatal.
  • The blue-ringed octopus injects its toxin by biting. The venom is held in salivary glands and the mouth of the octopus in on the underneath side in the middle of the body.
  • Since the blue-ringed octopus is not an aggressive marine animal, most cases of bites are from a person picking up and handling the octopus, or stepping on it in a sandy beach area. To avoid being bitten by a blue-ring octopus, never pick up or handle this marine animal, and when entering the ocean, shuffle your feet as you enter to avoid stepping on the octopus.

Blue-Ringed Octopus Bite Symptoms

The blue-ringed octopus bite is highly poisonous to humans. If you or someone you know has been bitten by a blue-ringed octopus, call 911 or activate the local medical emergency service in the area immediately.

  • Most bites cause minimal pain for the first 5-10 minutes then begin to throb and may get numb and involve the rest of the arm (or extremity) bitten.
  • Bleeding may be excessive
  • Numbness, nausea, vomiting, changes in vision, and difficulty swallowing.
  • After approximately 10 minutes, the victim may have difficulty breathing, become paralyzed, and require artificial ventilation until they can be transported to a hospital. This is often preceded by numbness or loss of feeling around the lips and mouth. If medical care is not provided emergently, respiratory failure may occur, which may lead in cardiac arrest, and death.
Medically Reviewed by a Doctor on 11/17/2017
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