While the IDS recommends fairly short courses of antibiotics, many patients, especially those with multiple infections and late-stage Lyme disease, require longer courses of antibiotics.
According to the CDC, patients treated with appropriate antibiotics in the early stages of Lyme disease usually recover rapidly and completely. Antibiotics commonly used for oral treatment of Borreliosis (Borrelia) include doxycycline, amoxicillin, or cefuroxime axetil. Patients with neurological or cardiac forms of illness may require intravenous treatment with drugs such as ceftriaxone or penicillin.
In terms of dosage, the CDC has adopted the guidelines of set out by the Infectious Diseases Society of America: For adults – Doxycycline (100 mg twice per day), amoxicillin (500 mg 3 times per day), or cefuroxime axetil (500 mg twice per day) for 14 days (range, 10-21 days for doxycycline and 14-21 days for amoxicillin or cefuroxime axetil). For children – amoxicillin (50 mg/kg per day in 3 divided doses [maximum of 500 mg per dose]), cefuroxime axetil (30 mg/kg per day in 2 divided doses [maximum of 500 mg per dose]), or, if the patient is ?8 years of age, doxycycline (4 mg/kg per day in 2 divided doses [maximum of 100 mg per dose]).
For adults who are allergic to, or who cannot tolerate the above antibiotics, the IDS recommends: azithromycin, 500 mg orally per day for 7-10 days; clarithromycin, 500 mg orally twice per day for 14-21 days (if the patient is not pregnant); or erythromycin, 500 mg orally 4 times per day for 14-21 days. The recommended dosages for children are as follows: azithromycin, 10 mg/kg per day (maximum of 500 mg per day); clarithromycin, 7.5 mg/kg twice per day (maximum of 500 mg per dose); or erythromycin, 12.5 mg/kg 4 times per day (maximum of 500 mg per dose).
While the IDSA recommends fairly short courses of antibiotics, many patients, especially those with multiple infections and late-stage Lyme disease, require longer courses of antibiotics. In a review of evidence-based therapies, the International Lyme and Associated Diseases Society (ILADS) found that given the enormous burden imposed by chronic and post-treatment Lyme disease, preventive treatment of 200 mg doxycycline is warranted in the case of exposure to a tick bite.
If an adult patient presents with the bull’s eye rash, ILADS recommends 4-6 weeks of amoxicillin 1500-2000 mg daily in divided doses, cefuroxime 500 mg twice daily or doxycycline 100 mg twice daily or a minimum of 21 days of azithromycin 250-500 mg daily. For children, ILADS recommends amoxicillin 50 mg/kg/day in three divided doses, with a maximal daily dose of 1500 mg; cefuroxime 20-30 mg/kg/day in two divided doses, with a maximal daily dose of 1000 mg and azithromycin 10 mg/kg on day 1 then 5-10 mg/kg daily, with a maximal daily dose of 500 mg. For children 8 years and older, doxycycline is an additional option. Doxycycline is dosed at 4 mg/kg/day in two divided doses, with a maximal daily dose of 200 mg. Higher daily doses of the individual agents may be appropriate in adolescents.
In cases in which symptoms persist, or the patient has had undiagnosed Lyme disease for a long period of time or has coinfections, Lyme specialists may recommend courses of treatment that can last from months to years. ILADS encourages clinicians to monitor patients closely for relapses, and for continuing symptoms, and to base treatment decisions on the needs of the patient. Patients, in their turn, should be informed about treatment risks and benefits. Throughout their recommendations, ILADS stresses the importance of discussing treatment options with patients “in the context of shared medical decision-making.”
Ixodes ticks can carry a number of pathogens, which means that anyone diagnosed with Borrelia may also be infected with Babesia, a malaria-like pathogen; Ehrlichia, a pathogen that infects cellular elements of peripheral blood, such as erythrocytes (red blood cells), leukocytes (white blood cells) and platelets; and Bartonella, which causes cat scratch fever. A less common but serious co-infection is the Powassan virus.
Treatment for babesiosis may be combination of two types of anti-parasite drugs, atovaquone (Mepron, Malarone) plus an antibiotic in the erythromycin familiy (azithromycin, clarithromycin, or telithromycin). Long-standing infections may need to be treated for several months, and relapses can occur and must be retreated. Patients with severe babesiosis may need to be treated with intravenous clindamycin and (oral) quinine.
Ehrlichisosis, and anaplasomis (caused by Anaplasma phagocytophilum, a rickettsial bacterium), are treated with tetracyclines. Oral doxycycline is normally prescribed at a dose of 100 mg every 12 hours, for 5-14 days. (Doxycycline is also recommended for children.) In severe cases, intravenous therapy is used or antibiotic treatment is extended. In all cases, treatment should be continued for at least 3-5 days after the fever subsides.” Rifampin is used in cases where doxycycline is contraindicated.
Bartonella, or cat scratch fever, is normally treated with tetracyclines, macrolides or aminoglycosides. For central nervous system infection, antibiotics that cross the blood brain barrier are necessary, and a combination of several antibiotics is usually recommended. Among the recommended treatments are azithromycin or doxycycline in combination with rifampin, clarithromycin or a fluoroquinolone. Most guidelines suggest that treatment should last for at least 4-6 weeks.
While infection with the Powassan virus is relatively rare, it is a serious infection that can cause Powassan encephalitis, a neurological disease that causes inflammation in the central nervous system. Roughly 10% of people who contract Powassan virus die of the infection. There is currently no treatment for Powassan virus, but people who contract it may need to be hospitalized to receive IV fluids and medications to reduce swelling in the brain.
John F. Anderson and Philip M. Armstrong. Prevalence and Genetic Characterization of Powassan Virus Strains Infecting Ixodes scapularis in Connecticut. Am J Trop Med Hyg. 2012 Oct 3; 87(4): 754-759. doi: 10.4269/ajtmh.2012.12-0294. PMCID: PMC3516331
CDC: Powassan virus
Columbia University Medical Center: Babesiosis.
Columbia University Medical Center: Ehrlichiosis.
Columbia University Medical Center: Bartonella.
Daniel J Cameron, Lorraine B Johnson, and Elizabeth L Maloney. Evidence assessments and guideline recommendations in Lyme disease: the clinical management of known tick bites, erythema migrans rashes and persistent disease. Informa Healthcare, September 2014, Vol. 12, No. 9, Pages 1103-1135 (doi:10.1586/14787210.2014.940900)
Gary P. Wormser, Raymond J. Dattwyler, Eugene D. Shapiro, John J. Halperin, Allen C. Steere, Mark S. Klempner, Peter J. Krause, Johan S. Bakken, Franc Strle, Gerold Stanek, Linda Bockenstedt, Durland Fish, J. Stephen Dumler, and Robert B. Nadelman. The Clinical Assessment, Treatment, and Prevention of Lyme Disease, Human Granulocytic Anaplasmosis, and Babesiosis: Clinical Practice Guidelines by the Infectious Diseases Society of America. Clin Infect Dis. (2006) 43 (9): 1089-1134. doi: 10.1086/508667
Last Updated: 4/23/15