No risk when duration of attachment <24 hrs
Adult: Doxycycline 200mg PO x1
Child >8: 4mg/kg up to 200mg PO x1
Give if all of the following are met:
Tick is adult/nymphal I. scapularis
Tick was attached >36 hours based on degree of engorgement or exposure time
Prophylaxis can be given within 72 hrs after time tick was removed
Local rate of infection in ticks >20%
Doxycycline is not contraindicated
Old vaccine has little to no efficacy after 1 year
Tick is adult/nymphal I. scapularis
Tick was attached >36 hours based on degree of engorgement or exposure time
Prophylaxis can be given within 72 hrs after time tick was removed
Local rate of infection in ticks >20%
Doxycycline is not contraindicated
Treat before serologic testing if endemic area if + erythema migrans rash
Doxycycline 100 mg PO BID x 10 days 
Acceptable for all pediatric patients when used for 21 days or less
Also treats human granulocytic ehrlichiosis
Amoxicillin 500 mg PO TID x 14 days 
Preferred in pregnant, lactating
Cefuroxime axetil 500 mg PO BID x 14 days 
Macrolides- not first line
Jarisch-Herxheimer like reaction can occur in first 24 hrs of treatment (fevers, chills, myalgia, tachycardia)
Doxycycline 100 mg PO BID x 10 days 
Acceptable for all pediatric patients when used for 21 days or less
Also treats human granulocytic ehrlichiosis
Amoxicillin 500 mg PO TID x 14 days 
Preferred in pregnant, lactating
Cefuroxime axetil 500 mg PO BID x 14 days 
Macrolides- not first line
Acceptable for all pediatric patients when used for 21 days or less
Also treats human granulocytic ehrlichiosis
Preferred in pregnant, lactating
Doxycycline (see above dosing)
Amoxicillin (See above dosing)
Ceftriaxone 2g IVq12h x 14-28 days
Doxycycline 200-400mg/d divided into two doses q day x 10-28 days
Preferred for facial palsy or<unk>  meningitis (lack of efficacy studies other medications)
Penicillin G, Cefotaxime
Doxycycline 200-400mg/d divided into two doses q day x 10-28 days
Preferred for facial palsy or<unk>  meningitis (lack of efficacy studies other medications)
Penicillin G, Cefotaxime
Preferred for facial palsy or<unk>  meningitis (lack of efficacy studies other medications)
Mild (1st degree AV with PR <0.3 sec)
Doxycycline/Amoxicillin PO
Severe (HIgh-degree AV block)
Ceftriaxone/Pen G IV
Doxycycline/Amoxicillin PO
Ceftriaxone/Pen G IV
Doxycycline, Amoxicillin PO, as effective as parenteral
Ceftriaxone/Pen G IV
Lyme disease
Enterovirus
Rabies
Hepatitis
Scarlet fever
Mononucleosis
Plague
Connective tissue disease