- Phylum Mollusca, Class Gastropoda, Family Conidae. These cones possess a detachable, dart-like radicular tooth or muscular proboscis. The venom is complex composed of two or more substances, one neuromuscular (causing sustained contractions), the other inhibits nerve excitability.
- Symptoms: Small puncture wound with localized ischemia (blanching), cyanosis (pale, bluish color), and edema (swelling). Severe pain, numbness, and tingling (paresthesias) of the mouth and lips is noted. Sometimes there is respiratory distress and paralysis.
- Treatment: Immobilize the limb, apply a pressure dressing, administer CPR if needed. Cleanse the puncture site, give analgesics and give tetanus prevention. Be prepared to support and monitor respiratory function.
- Phylum Mollusca, Class Cephalopeda. The salivary glands of the blue-ringed octopus produce a venom, maculotoxin, that has effects similar to tetradotoxin (fuji).
- Symptoms: The bite is usually painless, then is followed by painless paralysis. The pattern begins with abnormal sensations of the mouth, neck and head; followed by nausea, vomiting, shortness of breath and sometimes apnea ((lack of respirations).There can be visual disturbances, impaired speech and swallowing, and generalized weakness and paralysis. The duration is from 4 to 12 hours.
- Treatment: Immobilize the limb, apply pressure dressings, cleanse the bite, treat for tetanus and monitor the respiratory functions.
- Phylum Chordata, Class Chondrichthyes. These possess a serrated bony spine at the base of the dorsal surface of the tail. An integumentary sheath discharges venom when ruptured. Most injuries occur when the ray is stepped on, the tail is thrust upward and forward and fired into the foot or leg. The venom is thermolabile (deactivated with heat) and induces severe vasoconstriction.
- Symptoms: Intense pain is felt at the site; there is local ischemia (loss of blood supply), and edema. Edges are jagged, may contain pieces of spine and secondary infection is common. Systemic effects include salivation, sweating, vomiting, diarrhea, cramps, hypotension (low blood pressure), and cardiovascular collapse.
- Treatment: Irrigate and remove remaining spine. Immerse in hot (50 C) water until pain subsides. Give local or systemic pain relief. Cleanse, debride and suture the wound. Give tetanus protection, infection prophylaxis and monitor / support cardio-respiratory system as indicated.
Salt Water Catfish
The fins of the saltwater catfish have a complex toxin made up of a mix of high molecular weight proteins and low molecular weight compounds. Like many marine toxins, this venom is believed to be denatured at temperatures above 105 F.
Besides intense pain that appears to be out of proportion for the physical injury, systemic symptoms can occur but are rare. They include muscle cramps, tremor, fatigue, syncope and even CV collapse. Treatment in the ER consists of immersion of the body part in hot water at approx. 110 F, debridement (cleansing) of the wound completely and liberal irrigation with hot water. Tetanus coverage is provided. It’s a good idea to treat with antibiotics that cover Vibrio vulnificus, usually a 3rd gen cephalosporin.
Severe allergic reactions can occur. If you are in a boat and cannot get to hot water, a good preparation to use is a paste of baking soda and meat tenderizer. This paste is also said to be effective for jelly fish stings.
- Phylum Chordata, Class Osteich, Family Scorpaenidae. There are many species, including lionfish and stonefish. The venom is similar to stingray, is thermolabile and the stonefish is the most toxic. An antivenin is available throughthe Australia Commonwealth Serum Lab.
- Symptoms: Immediate intense pain, erythema, edema, cyanosis. Nausea, vomiting, hypotension, delirium and cardiovascular collapse.
- Treatment: Irrigate and remove debris. Immerse in hot water 30 to 90 minutes. Give analgesia and inject 1 ml. Emetine if available (50 mg/ml). Give stonefish antivenin if available. Provide antibiotics and tetanus prophylaxis
- Phylum Chordata, Class Reptilia, Order Squamata. The sea snake is an inquisitive but usually nonaggresive air-breathing snake. The venom is extremely toxic (2-10 times the cobra), and many bites are not envenomated. The venom is heat stable, is a nonenzymatic protein, and blocks acetylcholine.
- Symptoms: The bite is noted without symptoms as there is an initial latent period varying from 10 minutes to 6-8 hours. . There is the onset of malaise (bad feeling), anxiety and stiffness. Followed by aching and paralysis. Trismus (Jaw paralysis), ptosis (paralysis of eyelids) are common. Ten percent of untreated cases are fatal.
- Treatment: Immobilize the site of the bite. Hospitalize, obtain the antivenin and give CPR if needed. Try polyvalent land snake antivenom if specific not available. Hemodialysis can be helpful and respiratory support and control are often needed.