What is the treatment for a snake bite?

Snake Bite Treatment

Immediately activate emergency services, immobilize the bitten extremity, remove constricting items, and transport rapidly to a hospital for antivenom administration—the definitive treatment that must be given within hours to prevent death or severe morbidity. 1

Immediate Field Management (First 5 Minutes)

Universal Actions for ALL Snake Bites

• Activate emergency medical services immediately—time to antivenom is the single most important prognostic factor for survival 2, 1
• Completely immobilize the bitten extremity and keep it below heart level to minimize venom absorption through the lymphatic system 2, 3, 1
• Remove all rings, watches, jewelry, and constricting objects immediately before swelling develops, as progressive edema causes ischemic injury to digits 2, 3, 1
• Minimize all patient exertion during transport—walking or physical activity dramatically increases systemic venom absorption 2, 3, 1

Critical Geographic Distinction: Pressure Immobilization

• For sea snakes and coral snakes (neurotoxic venoms): Apply pressure immobilization bandaging at 40-70 mm Hg (upper extremity) or 55-70 mm Hg (lower extremity) around the entire length of the bitten limb 2
• For North American pit vipers (rattlesnakes, copperheads, cottonmouths): Do NOT use pressure immobilization—this worsens local tissue injury with cytotoxic venoms 1

What NOT to Do (Evidence-Based Harmful Practices)

• Do NOT apply ice or cold therapy—ineffective for venom removal and causes tissue injury 2, 1
• Do NOT use suction devices, incision, or mouth suction—ineffective at removing venom and causes additional tissue damage 2, 1
• Do NOT apply tourniquets—systematic reviews demonstrate they worsen local tissue injury without preventing systemic envenomation 2, 1
• Do NOT use electric shock therapy—both ineffective and potentially harmful 2, 1

Hospital-Based Definitive Treatment

Antivenom Administration

• Antivenom is the cornerstone and only definitive treatment for venomous snake bites 1, 4, 5
• Administer antivenom to all patients with confirmed or suspected envenomation showing any signs of toxicity (pain, swelling, ecchymoses, systemic symptoms, or abnormal laboratory findings within 30-60 minutes) 3, 5
• Antivenom is most effective when given within 4 hours of the bite 4
• Perform mandatory skin testing before antivenom administration to predict anaphylactic reactions 5, 6
• Have diphenhydramine and epinephrine immediately available during antivenom infusion for anaphylaxis management 5

Dosing by Severity

• Mild envenomation: Up to 5 vials of antivenom 5
• Moderate envenomation: 10-15 vials of antivenom 5
• Severe envenomation: 15-20 vials of antivenom 5

Adjunctive Hospital Management

• Administer broad-spectrum antibiotics to all envenomation grades 5, 7
• Provide tetanus prophylaxis if immunization status is uncertain 4, 5, 7
• Give plasma expanders, pain medication, and diazepam as supportive care 4
• Clean the wound with antiseptics 4

Monitoring Requirements

• Hospitalize for a minimum of 48 hours with continuous monitoring—neurotoxicity onset can be delayed up to 13 hours in coral snakes and sea snakes, with rapid progression once symptoms begin 2, 3
• Monitor continuously for neurotoxicity signs: muscle weakness, ptosis, difficulty swallowing, respiratory distress, altered mental status 2
• Monitor for respiratory compromise from the moment of bite—neurotoxicity can begin within minutes 3

Critical Clinical Pitfalls to Avoid

• Never assume no envenomation based on lack of local symptoms—coral snakes and sea snakes cause minimal local findings despite life-threatening systemic toxicity 2, 3, 1
• Never delay transport to attempt ineffective field interventions—this wastes critical time when antivenom timing determines survival 2, 3, 1
• Never discharge patients prematurely—neurotoxicity can be delayed up to 13 hours, requiring prolonged observation 3
• Never fail to remove constricting items early—progressive swelling leads to ischemic injury 1
• Never apply pressure immobilization for North American pit vipers—this technique is only for neurotoxic snakes and worsens cytotoxic venom injury 1

Snake Type-Specific Considerations

Pit Vipers (99% of US bites: rattlesnakes, copperheads, cottonmouths)

• Primary toxicity: Local tissue necrosis, pain, edema, ecchymoses at bite site, followed by cardiac, hematologic, renal, and pulmonary effects 4, 7
• Do NOT use pressure immobilization 1

Coral Snakes and Sea Snakes (1% of US bites)

• Primary toxicity: Neurotoxic effects with minimal to no local tissue injury 2, 3, 1
• DO use pressure immobilization bandaging 2
• Higher risk of delayed respiratory paralysis requiring intensive monitoring 2, 3