Lyme Disease Guidelines

Updated: May 17, 2023
  • Author: John O Meyerhoff, MD; Chief Editor: Herbert S Diamond, MD  more...
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Guidelines Summary

The Infectious Diseases Society of America, American Academy of Neurology, and American College of Rheumatology (IDSA/AAN/ACR) have published updated guidelines for the prevention, diagnosis, and treatment of Lyme disease. [6]

Diagnosis and prophylaxis

 IDSA/AAN/ACR recommendations regarding diagnosis of Lyme disease include the following:

  • Submit removed ticks for species identification.
  • Do not test removed Ixodes ticks for Borrelia burgdorferi, as the results do not reliably predict the likelihood of clinical infection.
  • Do not test asymptomatic patients for exposure to B burgdorferi after an Ixodes species tick bite


IDSA/AAN/ACR guidelines recommend limiting the use of prophylactic antibiotic therapy to adults and children within 72 hours of removal of an identified high-risk tick bite. To be considered high risk, a tick bite must meet all of the following 3 criteria:

  • The tick bite was from an identified Ixodes spp. vector species.
  • The tick bite occurred in a highly endemic area.
  • The tick was attached for ≥36 hours.

If a tick bite cannot be classified with a high level of certainty as a high-risk bite, the guidelines recommend a wait-and-watch approach. Antibiotic prophylaxis is not recommended for bites that are equivocal risk or low risk.

The recommended regimen for prophylaxis is a single oral dose of doxycycline, 200 mg for adults and 4.4 mg/kg (up to a maximum dose of 200 mg) for children.

Erythema migrans

In patients with potential tick exposure in a Lyme disease endemic area who have 1 or more skin lesions compatible with erythema migrans, the IDSA/AAN/ACR guidelines recommend clinical diagnosis rather than laboratory testing. For lesion(s) suggestive of, but atypical for, erythema migrans, the guidelines suggest antibody testing performed on an acute-phase serum sample rather than currently available direct detection methods such as polymerase chain reaction (PCR) or culture performed on blood or skin samples.

If the initial test result is negative, convalescent-phase serum testing may be considered, with the serum sample collected at least 2–3 weeks after collection of the acute-phase serum sample.

Recommended oral antibiotic regimens for treatment of patients with erythema migrans are as follows:

  • Doxycyline for 10 days
  • Amoxicillin for 14 days
  • Cefuroxime axetil for 14 days
  • Azithromycin (for patients unable to take doxycycline or beta-lactam antibiotics) for 5–10 days, with a 7-day course preferred in the United States

For patients who develop southern tick–associated rash illness (STARI)—an erythema migrans–like skin lesion following the bite of the lone star tick (Amblyomma americanum)—the guidelines make no recommendation for or against the use of antibiotics.

Testing for Lyme neuroborreliosis

When assessing patients for possible Lyme neuroborreliosis involving either the peripheral nervous system (PNS) or central nervous system (CNS), use serum antibody testing rather than PCR or culture of either cerebrospinal fluid (CSF). For suspected Lyme neuroborreliosis involving the central nervous system, obtain simultaneous samples of CSF and serum for determination of the CSF:serum antibody index, performed by a laboratory using validated methodology.

The guidelines recommend testing for Lyme disease in patients with 1 or more of the following acute neurologic presentations who have epidemiologically plausible exposure to ticks infected with B burgdorferi:

  • Meningitis
  • Painful radiculoneuritis
  • Mononeuropathy multiplex, including confluent mononeuropathy multiplex
  • Acute cranial neuropathies (particularly VII and VIII; less commonly III, V, VI, and others)
  • Evidence of spinal cord inflammation, particularly in association with painful radiculitis involving related spinal cord segments
  • Evidence of inflammation (rare)

The guidelines recommend against Lyme disease testing in patients with any of the following:

  • Other neurologic syndromes
  • Absence of a history providing other clinical or epidemiologic support for the diagnosis of Lyme disease
  • Typical amyotrophic lateral sclerosis
  • Relapsing-remitting multiple sclerosis
  • Parkinson disease
  • Dementia or cognitive decline
  • New-onset seizures
  • Nonspecific MRI white matter abnormalities confined to the brain in the absence of a history of other clinical or epidemiologic support for the diagnosis of Lyme disease
  • Psychiatric illness (in adults)
  • Developmental, behavioral, or psychiatric disorders (in children)

Treatment of neuroborreliosis

Recommended antibiotic regimens for Lyme disease–associated meningitis, cranial neuropathy, radiculoneuropathy, or with other PNS manifestations are 14-21 days of one of the following:

  • Intravenous (IV) ceftriaxone
  • IV cefotaxime
  • IV penicillin G
  • Oral doxycycline

The guidelines recommend using IV over oral antibiotics in patients with Lyme disease–associated parenchymal involvement of the brain or spinal cord.

Lyme carditis

The IDSA/AAN/ACR guidelines include the following suggestions and recommendations regarding Lyme carditis:

  • An electrocardiogram (ECG) is suggested in patients with signs or symptoms consistent with Lyme carditis (eg, dyspnea, edema, palpitations, lightheadedness, chest pain, syncope).
  • Hospital admission with continuous ECG monitoring is recommended in patients with, or at risk of, severe cardiac complications of Lyme disease (eg, PR prolongation  > 300 milliseconds, other arrhythmias, clinical manifestations of myopericarditis).
  • Testing for Lyme disease is recommended in patients with acute myocarditis/pericarditis of unknown cause in an appropriate epidemiologic setting.
  • The guidelines suggest against routine testing for Lyme disease in patients with chronic cardiomyopathy of unknown cause.

Lyme carditis treatment:

  • Temporary pacing modalities rather than implantion of a permanent pacemaker is recommended for patients with symptomatic bradycardia due to Lyme carditis that cannot be managed medically.
  • For outpatients with Lyme carditis, oral rather than IV antibiotics are suggested.
  • For hospitalized patients with Lyme carditis, the suggested strategy is to administer IV ceftriaxone until clinical improvement occurs, then switch to oral antibiotics to complete 14-21 days of treatment. Oral antibiotics recommended for Lyme carditis are doxycycline, amoxicillin, cefuroxime axetil, and azithromycin.

Lyme arthritis

The IDSA/AAN/ACR guidelines include the following suggestions and recommendations regarding Lyme arthritis:

  • For diagnosis of Lyme arthritis, serum antibody testing is strongly recommended over PCR or culture of blood or synovial fluid/tissue.
  • If more definitive information is required to guide treatment decisions in seropositive patients with possible Lyme arthritis, PCR (rather than Borrelia culture) of synovial fluid or tissue is recommended.
  • Oral antibiotic therapy for 28 days is recommended for treatment of Lyme arthritis.
  • In patients whose Lyme arthritis shows a partial response (mild residual joint swelling) to a first course of oral antibiotic, the guidelines make no recommendation for or against a second course of antibiotics versus observation.
  • In patients whose Lyme arthritis shows no or minimal response (moderate to severe joint swelling with minimal reduction of the joint effusion) to a first course of oral antibiotics, a 2- to 4-week course of IV ceftriaxone is suggested over a second course of oral antibiotics.
  • For postantibiotic Lyme arthritis (ie, after failure of 1 course of oral antibiotics and 1 course of IV antibiotics), the guidelines suggest referral to a rheumatologist or other trained specialist for consideration of the use of disease-modifying antirheumatic drugs (DMARDs), biologic agents, intra-articular steroids, or arthroscopic synovectomy. Antibiotic therapy for longer than 8 weeks is not expected to provide additional benefit to patients with persistent arthritis if that treatment has included 1 course of IV therapy.