What is the recommended treatment for a bullseye rash appearing after a tick bite?

Treatment for Bullseye Rash After Tick Bite

A bullseye rash (erythema migrans) appearing after a tick bite should be treated with a 10-day course of doxycycline or a 14-day course of amoxicillin or cefuroxime axetil, as this indicates likely Lyme disease infection. 1

Diagnosis

• Erythema migrans (bullseye rash) is pathognomonic for Lyme disease in patients with potential tick exposure in endemic areas 1
• Clinical diagnosis is recommended rather than laboratory testing for typical erythema migrans 1
• Serological tests are not useful at this early stage of infection as they may be negative 2

First-Line Treatment Options

• Doxycycline: 100 mg twice daily for 10 days 1
• Amoxicillin: 500 mg three or four times daily for 14 days 1, 3
• Cefuroxime axetil: 500 mg twice daily for 14 days 1

Special Populations

• For pregnant women, children under 8 years, or those who cannot take doxycycline:
  • Amoxicillin is the preferred alternative 1, 4
  • Azithromycin (5-10 days, preferably 7 days) can be used if patients cannot take both doxycycline and beta-lactams 1
  • Doxycycline is contraindicated in pregnant/breastfeeding women and children <8 years due to risk of tooth and bone disorders 4, 2

Important Considerations

• Treatment should begin promptly upon recognition of the bullseye rash to prevent progression to later stages of Lyme disease 2
• Shorter courses (10 days of doxycycline or 14 days of amoxicillin/cefuroxime) are recommended over longer treatment courses 1
• Monitor for potential side effects:
  • Doxycycline: photosensitivity, esophageal irritation 4
  • Amoxicillin: rash, diarrhea 1

Prevention of Future Tick Bites

• Use EPA-registered repellents (DEET, picaridin, IR3535, oil of lemon eucalyptus) 1, 5
• Wear protective clothing 5, 6
• Perform daily tick checks 5
• Remove ticks promptly using fine-tipped tweezers 1

Follow-up

• Patients should monitor for persistent or new symptoms that could indicate treatment failure or progression to later stages of Lyme disease 3
• Most patients (approximately 90%) will have complete resolution of symptoms with appropriate antibiotic therapy 2

Distinguishing STARI from Lyme Disease

• In certain geographic regions, Southern tick-associated rash illness (STARI) may present similarly to Lyme disease 1
• When STARI cannot be distinguished from Lyme disease in areas endemic for both conditions, treatment for Lyme disease is indicated 1

Early treatment with appropriate antibiotics is highly effective at preventing progression to later, more serious stages of Lyme disease, making prompt recognition and treatment of the bullseye rash essential 3, 2.