Envenement

Envenement is a term used to refer to envenomation, the process by which venom is delivered by a venomous animal into a person or animal. It most often results from bites by snakes or stings from insects and marine creatures, but can also occur via spines or other delivery structures. The venom contains toxins that disrupt cellular processes, affecting the nervous system, blood coagulation, or local tissue.

Causes and mechanisms: Venomous animals include snakes, scorpions, spiders, jellyfish, cone snails, stingrays, and some marine worms. Venom is injected through fangs, stingers, or specialized spines. Toxins may be neurotoxic, hemotoxic, cardiotoxic, cytotoxic, or a combination, producing pain, swelling, and sometimes systemic organ dysfunction.

Clinical features and diagnosis: Presentation depends on species, dose, and individual factors. Local signs include severe pain, swelling, and tissue injury; systemic signs may include dizziness, weakness, nausea, difficulty breathing, abnormal heart rhythm, or bleeding abnormalities. Diagnosis relies on exposure history, physical examination, and, when possible, identification of the animal.

Management: Initial care emphasizes safety and rapid medical contact. Immobilize the affected limb, keep it still and at heart level if feasible, remove constricting items. Do not cut, suck, or apply ice unless advised for a specific species. Antivenom is the specific treatment for many envenomations; supportive care includes pain relief, fluids, wound care, and monitoring for complications.

Prevention and prognosis: Prevention focuses on avoiding venomous encounters and using protective gear. Prognosis varies with venom type, dose, and access to timely treatment; many envenomations are mild, while others can be fatal. See also: envenomation, venom, venomous animal, antivenom.