Guideline for Management of Non‑Venomous Insect Bites

Assessment & Classification

• Patients with non‑venomous insect bites should be classified into three reaction types:
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Simple Local Reactions

• No specific therapy is required for uncomplicated simple local reactions.
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• When symptoms are bothersome, cold compresses can be applied to lessen pain and swelling.
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• Second‑generation oral antihistamines are recommended to reduce itching.
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• Oral analgesics may be used for pain relief.
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Large Local Reactions

• Management includes oral antihistamines for pruritus and cold compresses for pain and swelling.
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• A short course of oral corticosteroids is advised for patients with extensive swelling or a history of large local reactions.
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• Antibiotics are not indicated unless there is clear evidence of a secondary bacterial infection (e.g., purulent drainage, expanding cellulitis beyond the reaction zone).
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• The swelling and lymphangitis seen in large local reactions result from allergic inflammation and mediator release, not infection; therefore, routine antibiotic use is inappropriate.
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Systemic Reactions & Escalation

• Immediate referral to an emergency department or allergist is required if any systemic symptoms develop (urticaria beyond the bite site, respiratory distress, throat swelling, hypotension, or gastrointestinal symptoms).
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• Delay in epinephrine administration during systemic reactions is associated with fatal outcomes; epinephrine should be given promptly.
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• Patients with a history of prior systemic reactions to insect bites should be escalated to higher‑level care.
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Fire Ant Bites (Special Consideration)

• Sterile pseudopustules appear within 24 h and are pathognomonic for fire‑ant stings.
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• The vesicles should be left intact and kept clean to minimize the risk of secondary infection.
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• The vesicle contents consist of necrotic tissue and are not infected; secondary infection is uncommon but possible.
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Preventive Measures

• Advise patients to wear protective clothing when in high‑risk environments.
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• Recommend avoiding walking barefoot outdoors to reduce exposure.
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Contraindicated Practices

• Do not prescribe antibiotics for uncomplicated simple or large local reactions.
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• Do not apply topical ammonia, isopropanol, or ethanol to bite sites, as these agents can cause harm.
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• Do not delay epinephrine administration when systemic symptoms are present.
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