What medication should be given to a female with a wasp sting to treat swelling?

Treatment of Wasp Sting Swelling in Females

For localized swelling from a wasp sting, administer oral antihistamines and apply cold compresses, with topical corticosteroids for persistent inflammation; reserve oral corticosteroids for large local reactions with extensive swelling. 1

Immediate Management

Stinger Removal (If Present)

• Remove any visible stinger within 60 seconds by scraping with a fingernail or plucking—speed matters more than method, as venom delivery continues for up to 60 seconds 1
• Wash the area with soap and water after removal 1

Treatment Algorithm Based on Reaction Type

For Simple Local Swelling (Most Common)

• Apply cold compresses or ice packs to reduce pain and swelling 2, 1
• Administer oral antihistamines (e.g., diphenhydramine, cetirizine) to reduce itching and swelling 2, 1
• Apply topical corticosteroids directly to the sting site for local inflammation and itching 1, 3
• Give oral acetaminophen or ibuprofen for pain relief 1
• Most local reactions resolve within hours to days without treatment 2

For Large Local Reactions (Swelling >10 cm, Lasting 5-10 Days)

• Initiate a short course of oral corticosteroids (e.g., prednisone 0.5 mg/kg) promptly within the first 24-48 hours to limit progression of swelling 1, 3
• Continue cold compresses, oral antihistamines, and analgesics as above 2
• The evidence for oral corticosteroids is based on clinical experience rather than controlled trials, but they are widely used and supported by expert consensus 2, 1

Critical Pitfalls to Avoid

Do NOT Prescribe Antibiotics

• Swelling is caused by allergic inflammation and mediator release, NOT infection 2, 1
• Antibiotics are only indicated if there is clear evidence of secondary infection (rare) 2
• This is a common misdiagnosis that leads to unnecessary antibiotic use 2

Recognize Systemic Reactions Requiring Epinephrine

• If the patient develops symptoms beyond the sting site (urticaria elsewhere, throat swelling, difficulty breathing, lightheadedness, hypotension), this is anaphylaxis requiring immediate intramuscular epinephrine 0.3-0.5 mg in the anterolateral thigh 1, 4, 5
• Antihistamines and corticosteroids are NOT substitutes for epinephrine in anaphylaxis and play no role in acute management 1, 4
• Delayed epinephrine administration is associated with fatal outcomes 1, 4

Post-Treatment Considerations

Follow-Up and Prevention

• Large local reactions are usually self-limited and rarely progress to systemic reactions 2
• Patients with large local reactions have approximately 10% risk of systemic reaction with future stings 2
• Consider prescribing an epinephrine autoinjector for patients with large local reactions who have high exposure risk or anxiety about future stings, though this is optional 2
• Most patients with simple local or large local reactions do NOT require allergy testing or venom immunotherapy 2

Special Circumstances

• Eye stings (to the eye itself, not just eyelid) require immediate ophthalmology evaluation due to risk of permanent vision loss 1, 4
• Multiple stings (typically >100) can cause toxic reactions from massive envenomation even in non-allergic individuals 1, 4