Randomised controlled trials (RCTs) that compared antibiotic prophylaxis with placebo, in patients who were enrolled within 72 hours following an Ixodes tick bite and who had no clinical evidence of Lyme disease at enrolment, were eligible for inclusion.
The review outcome was the incidence of Lyme disease.
The included trials used the following antibiotics: penicillin (1,000mg/day for 10 days), amoxicillin (750mg/day for 10 days), tetracycline (1,000mg/day for 10 days) and doxycycline (200mg/day for one day). All the included trials were conducted in areas where Lyme disease was endemic. Most of the included trials recruited both adults and children; one trial recruited only children. The percentage of men in the included trials ranged from 35.7 to 53.3%.
The authors did not state how many reviewers assessed studies for inclusion.