What is the first‑line management of a wasp sting in an adult patient with no known allergy?

Wasp Sting Management in Adults Without Known Allergy

For an uncomplicated wasp sting in an adult with no known allergy, no treatment is usually required, but symptomatic management with cold compresses and oral antihistamines effectively addresses local pain, swelling, and itching. 1

Immediate Assessment

• Remove the stinger immediately if present by flicking or scraping it away with a fingernail within 10-20 seconds to prevent additional venom injection—avoid grasping the venom sac as this injects more venom. 1
• Assess for signs of systemic reaction (urticaria beyond the sting site, angioedema, respiratory distress, hypotension, gastrointestinal symptoms) which would require immediate epinephrine administration. 1, 2

Treatment of Simple Local Reactions

Most wasp stings cause transient localized reactions with pain, swelling, and redness that resolve within hours to days and require minimal intervention. 1

• Apply cold compresses to the sting site to reduce local pain and swelling. 1, 2
• Administer oral antihistamines to reduce itching and pain associated with the cutaneous reaction. 1, 2
• Provide oral analgesics for pain management as needed. 2
• Elevate the affected limb if swelling is significant. 2

Management of Large Local Reactions

If extensive erythema and swelling extends significantly from the sting site (typically peaking at 24-48 hours and lasting up to a week or more):

• Continue cold compresses and oral antihistamines. 1
• Consider a short course of oral corticosteroids for severe cases with extensive swelling, particularly if initiated promptly within the first 24-48 hours to limit progression. 1, 2, 3
• Do not prescribe antibiotics unless clear signs of secondary bacterial infection develop (progressive redness, increasing pain, purulent discharge, fever, warmth and tenderness)—the swelling is caused by allergic inflammation, not infection. 1, 2, 3

Critical Pitfalls to Avoid

• Never delay epinephrine if any systemic symptoms develop—antihistamines and corticosteroids are NOT substitutes for epinephrine in anaphylaxis, and delayed administration has been associated with fatal reactions. 1, 2, 3
• Do not routinely prescribe antibiotics for large local reactions, as this represents allergic inflammation rather than infection. 1, 2
• Do not grasp and pull out a stinger by the venom sac, as this injects additional venom. 1

When to Refer to Allergist

• Any patient who develops systemic symptoms (even mild cutaneous reactions like widespread urticaria) should be referred to an allergist-immunologist for venom-specific IgE testing and consideration of venom immunotherapy (VIT), which reduces future systemic reaction risk from 25-70% to less than 5%. 1, 4, 2, 3
• Patients with large local reactions and frequent unavoidable exposure may also benefit from allergist referral. 1, 2

Patient Education

• Instruct patients to monitor for delayed systemic symptoms over the next 24-48 hours. 2
• Educate on avoidance measures including not walking barefoot outdoors, wearing protective clothing, and avoiding scented products. 4
• For patients who develop any systemic symptoms, prescribe an epinephrine autoinjector and provide training on its use before discharge. 4, 2, 3