Blue-Ringed Octopus

 First aid for blue-ringed octopus bite is pressure-immobilisation.

The blue-ringed octopus’s salivary glands contain tetrodotoxin, which causes motor paralysis due to neuronal sodium channel blockade.

Signs and Symptoms

The initial bite is not painful, and may be unnoticed. Within about 10 minutes, however, symptoms of envenomation begin to develop, including weakness and numbness around the face, accompanied by nausea and vomiting. In a single case, cerebellar effects were also noted. Severe envenomations may progress rapidly to generalised flaccid paralysis and respiratory failure. Death may occur in as little as thirty minutes.

Treatment

The patient may be completely paralysed, sometimes with fixed dilated pupils, but the sensorium remains intact until hypoxia or hypercapnia supervene, and care should be taken to avoid negative remarks which may distress the alert but paralysed patient. Prolonged artificial respiration may be required before medical aid may be reached. Respiratory failure or the risk of pulmonary aspiration are indications for endotracheal intubation and mechanical ventilation until the effects of the venom wear off, usually within several hours to days. There is no antivenom available.