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Snake and scorpion envenomation
In viper bites, give supportive care, watch for progressive swelling, coagulopathy and systemic signs, and give antivenom when they appear; in yellow scorpion stings, mainly in children, the danger is an autonomic storm with pulmonary oedema and cardiac injury, and treatment is supportive in intensive care.
Why it matters in the exam
In Israel the common venomous snake is the Palestine viper, whose venom mainly causes spreading local swelling, bleeding and coagulopathy, and in severe cases hypotension, vomiting, diarrhoea and facial oedema. Questions test the correct first aid — reassurance, immobilising the limb and transfer — and the indications for antivenom: systemic signs, swelling that progresses beyond the nearest joint, or coagulopathy.
Standard distractors are a tourniquet, incision and suction of the venom, ice and routine antibiotics. A bitten patient is observed for at least 24 hours even when there are no signs at first, with repeated coagulation tests and blood counts, because envenomation can progress late. Tetanus status must be checked.
In a yellow scorpion sting the local pain is severe, but young children may develop a storm of the autonomic nervous system: sweating, salivation, vomiting, hypertension or hypotension, arrhythmias, pulmonary oedema and myocardial injury. A child with systemic signs is admitted to intensive care; treatment is supportive, and drugs such as prazosin are used for hypertension. In adults the picture is usually local and managed with analgesia and short observation.
Key points
- Viper: spreading swelling, bleeding and coagulopathy, shock.
- First aid: reassurance and immobilisation; no tourniquet, incision or suction.
- At least 24 hours of observation and repeated coagulation tests.
- Antivenom for systemic signs, swelling beyond the joint or coagulopathy.
- Yellow scorpion in children: autonomic storm, pulmonary oedema, intensive care.
Summary table
| Situation | Signs | Danger | Treatment |
|---|---|---|---|
| Viper bite, mild envenomation | Local pain and swelling only | Late progression | Immobilisation, 24 hours of observation, repeated coagulation tests |
| Viper bite, significant envenomation | Swelling beyond the joint, vomiting, hypotension, facial oedema, bleeding | Shock, coagulopathy | Antivenom, fluids, support |
| Scorpion sting in an adult | Severe local pain | Low | Analgesia, short observation |
| Scorpion sting in a child | Sweating, salivation, vomiting, hypertension, pulmonary oedema | Autonomic storm, cardiac injury | Intensive care, support, prazosin for hypertension |
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Sources
- WHO Guidelines for the management of snakebites, 2nd edition (2016) — Clinical management and antivenom
- Tintinalli's Emergency Medicine: A Comprehensive Study Guide, 9th edition (2020) — Reptile bites; Arthropod bites and stings
- Goldfrank's Toxicologic Emergencies, 11th edition (2019) — Native (US) and exotic venomous snakes; Arthropods
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.