What is the treatment for an ant bite?

Treatment of Ant Bites

The treatment for ant bites includes applying cold compresses, topical antihistamines, topical corticosteroids, and oral antihistamines for symptom relief, while large local reactions may require a brief course of oral corticosteroids. 1

Initial Management of Ant Bites

Local Reactions

For typical ant bites with local reactions:

• Clean the area thoroughly with soap and water 1
• Apply cold compresses to reduce swelling and inflammation 1
• Use topical treatments:
  • Topical antihistamines for itching relief 1
  • Topical corticosteroids (such as hydrocortisone) to reduce inflammation 2
  • Consider concentrated heat application for 2-5 minutes to reduce inflammation, pain, and itching 1
• Take oral antihistamines for itching control 1
• Use acetaminophen or NSAIDs for pain relief if needed 1

Large Local Reactions

For large local reactions to ant bites:

• Follow all steps for local reactions
• Consider a brief course of oral corticosteroids in severe cases 3
• Monitor for signs of infection (increasing redness, warmth, swelling, pain)
• Note that antibiotics are usually not necessary unless there are signs of secondary infection 3

Systemic Reactions and Anaphylaxis

Ant stings, particularly from fire ants, can cause severe allergic reactions including anaphylaxis 4, 5:

• For systemic reactions, immediate treatment with epinephrine is crucial 3, 1
  • Adult dosage: 0.3-0.5 mg intramuscularly into anterolateral thigh
  • Children ≥30 kg: 0.3-0.5 mL intramuscularly into anterolateral thigh
• Provide supportive therapy and transport to an emergency department 3
• Fatal reactions have been associated with delay in epinephrine administration 3

Follow-up Care

After an ant bite with systemic reaction:

• Refer to an allergist-immunologist for evaluation 3, 1
• Consider venom immunotherapy (VIT) for those with history of systemic reactions and positive specific IgE tests 3
• Patients with history of systemic reactions should:
  • Carry self-injectable epinephrine and know how to use it 3
  • Consider obtaining medical identification jewelry 3
  • Be educated on insect avoidance measures 3

Prevention of Ant Bites

Preventive measures include:

• Avoid brightly colored clothing and strong-smelling materials 1
• Wear protective clothing in high-risk areas 1
• Apply DEET-containing repellents (10-30% concentration) to skin and clothing 1
• Remove ant nests from living areas when possible 1
• Avoid areas with high grass and weeds 1

Special Considerations

• Fire ant bites typically cause sterile pustules due to piperidine alkaloids in their venom 4
• Black ants (Samsum ants) can also trigger allergic reactions in certain regions 6
• Some patients may develop cold-induced urticaria following ant bite-induced anaphylaxis 6
• Patients with a history of severe anaphylaxis to insect stings may need indefinite venom immunotherapy 3

Pitfalls and Caveats

• Don't delay epinephrine administration in cases of systemic reactions, as this is associated with fatal outcomes 3
• Don't prescribe antibiotics routinely for uncomplicated ant bites 3, 1
• Don't overlook the possibility of delayed reactions (serum sickness, vasculitis) which can occur more than 4 hours after ant stings 4
• Don't assume all ant species cause allergic reactions; only certain species like Solenopsis (fire ants), Myrmecia, and Pachycondyla typically cause allergic reactions 4