What is the recommended immediate management of a scorpion sting in north India?

Treatment of Scorpion Sting in North India

For scorpion stings in North India, immediately call emergency services if systemic symptoms develop (difficulty breathing, muscle rigidity, excessive salivation, altered consciousness), administer scorpion antivenom (Anascorp: 3 vials IV over 10 minutes) for any clinical signs of envenomation, and use prazosin (30 mcg/kg every 6 hours) with dobutamine for cardiovascular complications—this is critical because the Indian red scorpion (Mesobuthus tamulus) prevalent in this region causes life-threatening catecholamine release leading to hypertension, myocarditis, and acute pulmonary edema. 1, 2, 3, 4, 5

Immediate Assessment and Emergency Response

Call Emergency Services Immediately If:

• Difficulty breathing or respiratory distress develops 1, 2
• Loss of muscle control or muscle rigidity occurs 2, 1
• Roving or abnormal eye movements present 2
• Slurred speech develops 2
• Excessive salivation or frothing at the mouth 2
• Vomiting occurs 2
• Dizziness, confusion, or altered consciousness 1
• Tachycardia (heart rate 130-215/min), hypertension (BP 100-137 mmHg), or signs of cardiac involvement 4, 3

Critical Context: The Indian red scorpion is one of the world's deadliest scorpions, broadly distributed in western Maharashtra, Saurashtra, Kerala, Andhra Pradesh, Tamil Nadu, and Karnataka, with fatal envenomations primarily recorded in the Konkan region of Maharashtra. 3 This species causes severe systemic manifestations through catecholamine release. 3, 4

Antivenom Administration (First-Line for Systemic Envenomation)

Initial Dose:

• Administer 3 vials of scorpion antivenom (Anascorp) IV immediately for any clinical signs of envenomation 2
• Reconstitute each vial with 5 mL sterile normal saline, combine all 3 vials, dilute to total 50 mL with normal saline 2
• Infuse IV over 10 minutes 2
• Monitor closely during and up to 60 minutes post-infusion 2

Additional Doses:

• If symptoms persist after 60 minutes, administer 1 additional vial at 30-60 minute intervals 2
• Each additional vial: reconstitute with 5 mL saline, dilute to 50 mL, infuse over 10 minutes 2

Antivenom Precautions:

• Have epinephrine, corticosteroids, and diphenhydramine ready for potential anaphylaxis 2
• Patients with horse protein allergies are at particular risk 2
• Monitor for delayed serum sickness (rash, fever, myalgia, arthralgia) in follow-up visits 2

Important Limitation: Scorpion-specific antivenoms have exhibited poor immunorecognition and neutralization of the low molecular mass toxins that cause most Indian red scorpion pathology. 3 However, antivenom remains the preferred treatment and should be administered promptly. 3

Cardiovascular Management (Critical for Indian Red Scorpion)

Prazosin Protocol:

• Administer prazosin 30 mcg/kg/dose if patient presents within 4 hours of sting 5
• Continue prazosin every 6 hours until recovery if signs of envenomation present 5
• Prazosin counteracts the catecholamine-induced hypertension characteristic of Indian red scorpion stings 4, 5

For Acute Pulmonary Edema (APE) or Left Ventricular Failure:

• Dobutamine infusion for inotropic support 4, 5
• Sodium nitroprusside drip for afterload reduction 4, 5
• Digoxin, diuretics, and aminophylline as adjuncts for refractory myocardial failure 4

Evidence Strength: A protocol-guided therapy using prazosin and dobutamine significantly reduced overall mortality (p<0.0155) and deaths associated with acute pulmonary edema (p<0.0001) in Indian children with scorpion stings. 5 Mortality was particularly high in patients who received steroids and antihistamines outside the hospital or who presented late (>4 hours). 5

Local Wound Care and Pain Management

Immediate First Aid:

• Thoroughly irrigate the sting site with copious warm or room temperature water until no foreign matter remains 1
• Remove rings and constricting objects from the affected extremity immediately, as swelling may cause constriction 1
• Apply ice with a clean barrier between ice and skin for local pain relief 1
• Apply antibiotic ointment and cover with clean occlusive dressing 1

Pain Control:

• Over-the-counter acetaminophen or NSAIDs for systemic pain relief 1
• Topical lidocaine 5% if skin is intact 1

What NOT to Do (Critical Pitfalls)

• Do NOT apply suction to the sting site—this is ineffective and potentially harmful 1, 6
• Do NOT apply tourniquets or pressure immobilization bandages—these may worsen tissue injury and are not recommended for North American scorpions 6, 1
• Do NOT assume antibiotics are needed for swelling—swelling is caused by mediator release, not infection 1
• Do NOT administer steroids and antihistamines as primary treatment—these were associated with higher mortality in Indian studies 5

Monitoring and Follow-Up

Observation Period:

• Observe all patients for at least 24 hours, as most severe reactions occur soon after envenomation 1
• Most patients with local symptoms only recover completely within 24-48 hours 1

Complications to Monitor:

• Myocarditis (occurs due to toxin and excessive catecholamine) 5, 3
• Acute pulmonary edema (nearly half of children with acute myocarditis develop APE) 5
• Encephalopathy 5
• Cerebrovascular complications (intracranial hemorrhages from acute hypertension, cerebral infarctions from hypoperfusion or cardiogenic embolism) 7
• Coagulopathy 7

Signs Requiring Immediate Medical Attention:

• Progressive erythema extending beyond initial sting site 1
• Purulent discharge 1
• Systemic signs of infection (fever, elevated WBC) 1
• Any neurological symptoms 7

Special Considerations for North India

Regional Context: The Indian red scorpion (Mesobuthus tamulus) is distributed throughout the Indian sub-continent, including eastern Pakistan, eastern Nepal, and Sri Lanka, with broad distribution in western Maharashtra, Saurashtra, Kerala, Andhra Pradesh, Tamil Nadu, and Karnataka. 3 Fatal envenomations have been recorded primarily in the Konkan region of Maharashtra. 3

Pathophysiology: Indian red scorpion venom induces massive catecholamine release, leading to tachycardia, mydriasis, hyperglycemia, hypertension, toxic myocarditis, cardiac failure, and pulmonary edema. 3 The venom proteome comprises 110 proteins, with significant pharmacological activity from low molecular mass Na+ and K+ ion channel toxins. 3

Pediatric Vulnerability: Children are at particularly high risk for severe complications and death. 5 Aggressive management of acute pulmonary edema and early prazosin administration are critical in this population. 5