Cone snails, also referred to as cone shells or cone fish, are venomous predatory marine gastropod molluscs capable of inflicting a painful, dangerous sting to humans. They may be found in wide distributions throughout oceans and seas worldwide. Cone snails prey on marine worms and fish, using their venom apparatus to inject the victim with paralytic toxins. The cone snail uses a dart-like tooth that fires out from the shell. Many have beautiful patterns on the shell, making them attractive for unsuspecting divers to collect. When disturbed, the snail may deploy its harpoon like tooth and envenomate the handler. Smaller species inflict a sting similar to that of a wasp, but envenomations from larger species may cause intense pain, swelling, paresthesias, and vomiting. Rarely, severe envenomations may progress to muscle paralysis, respiratory failure, and death.
Cone Snail. The beautiful shells of the cone snail make it attractive for divers to collect. Envenomations commonly occur on the hand and fingers of unsuspecting victims due to handling the snail. (Photo contributor: Kevin J. Knoop, MD, MS.)
Geographic Cone Snail. This cone snail is seen in full view with tentacles, water siphon, and short pharynx (proboscis) visible. The geographic cone snail is highly venomous with a potentially fatal sting. (Photo contributor: Shawn Miller.)
Cone Snail (Old). As cone snails age, the shells may become covered in adherent materials, making them difficult to see and increasing the risk of inadvertent contact. (Photo contributor: Kevin J. Knoop, MD, MS.)
Management and Disposition
Cone snail venom is heat-labile. Initial management consists of hot water immersion similar to the treatment of scorpionfish stings. Rebound pain is common and is treated with repeated hot water immersion. Inspect the wound for foreign material, and perform thorough warm saline irrigation. Severe pain may be treated with local injection of lidocaine without epinephrine and with opiate analgesia. Consider antibiotic prophylaxis in high-risk wounds and address tetanus status.
Cone snail venom is heat-labile. Hot water immersion is effective in treating pain and inactivating venom.
Although fatal cone snail envenomations are rare, severe stings may cause death due to rapid onset of respiratory paralysis.