Impact of pharmacist-led prescribing for Lyme chemoprophylaxis on emergency department visits

Abstract Background: All regions of Nova Scotia (NS) are considered at high risk for Lyme disease. Pharmacists in NS gained authority to prescribe chemoprophylaxis for the prevention of Lyme disease after a tick bite in August 2021. Objectives: Our primary objective was to compare the frequency of emergency department (ED) visits for a tick bite before and after implementation of this expanded scope. Methods: A retrospective study using a pre–post design compared ED visits for tick bites 1.5 years before and 1.5 years after implementation of pharmacist prescribing. Patients who were assessed for a tick bite in 3 EDs were eligible for inclusion. Patients with active infection were excluded. Medical records were reviewed by research assistants. Descriptive statistics were used to summarize the data, and proportions of ED visits for tick bites were compared using the Chi-square test. Results: A total of 1019 patient encounters for tick bites (617 pre-intervention vs 402 post-intervention) met inclusion criteria across 3 EDs. Of these, 67.7% (690/1019) resulted in a prescription for a single dose of doxycycline to prevent Lyme disease. After implementation, the frequency of patient encounters for tick bites declined by about half (617 encounters in 88,512 ED visits pre-intervention vs 402 encounters in 115,847 ED visits post-intervention [p < 0.0001]). Discussion: After implementation of pharmacist prescribing for Lyme chemoprophylaxis, there was a decrease in patients visiting the ED for tick bites. Conclusion: Enabling pharmacist scope to include management of tick bites may alleviate some burden on local EDs in communities with high risk of Lyme disease.