Envenomation

Envenomation refers to the injection of venom by a venomous animal into a person, typically through a bite or sting. It encompasses envenomation from snakes, spiders, scorpions, and marine organisms such as jellyfish and cone snails, as well as other venomous species. It is distinct from poisoning, which results from ingestion, inhalation, or skin absorption of toxins.

Venoms are complex mixtures of enzymes, peptides, and other molecules that disrupt cellular processes and bodily systems. They can cause local tissue injury and swelling, as well as systemic effects such as neurotoxicity, cytotoxicity, hemotoxicity, or cardiotoxicity. The specific effects depend on the venom’s composition, dose, site of exposure, and the victim’s health and age.

Clinical presentation varies by the responsible species but often includes local pain, swelling, numbness, or tissue damage at the site of contact. Systemic symptoms may involve weakness, difficulty breathing, dizziness, changes in heart rate or blood pressure, bleeding abnormalities, or paralysis. Onset ranges from minutes to hours, and some venomous exposures can be life-threatening without timely treatment. Diagnosis is clinical, supported by species identification when possible and, in some cases, laboratory tests to monitor organ function.

First aid focuses on minimizing venom spread and obtaining medical care. Measure is to call emergency services, immobilize the affected limb, keep the patient calm and still, remove constrictive items, and clean the area with soap and water. Do not apply tourniquets, incisions, or suction. In hospitals, management may include antivenom for certain bites or stings, along with supportive care, pain control, wound care, and tetanus prophylaxis. Prognosis depends on the amount of venom, rapidity of treatment, and the victim’s overall health. Prevention centers on avoiding contact with venomous animals and wearing protective clothing in high-risk areas.