Research in Action: Evaluating Pharmacist Antibiotic Prescribing in Ontario

On January 1, 2023, Ontario expanded pharmacists’ scope of practice, authorizing them to prescribe medications for 13 minor ailments, including specific antibiotics for uncomplicated urinary tract infections (UTIs) and Lyme disease prophylaxis following a high‑risk tick bite. A new study led by Public Health Ontario (PHO) researchers, Valerie Leung and Drs. Bradley Langford, Kevin Schwartz, Kevin Brown, and Nick Daneman published in BMJ Open examines how this policy change has influenced antibiotic prescribing patterns across the province, and what it may mean for antimicrobial stewardship and access to care.

The study analyzed pharmacy billing claims and community antibiotic prescribing data before and after policy implementation, providing one of the first population‑level evaluations of pharmacist antibiotic prescribing in Ontario.

Why is this study important?
Antimicrobial resistance remains a major public health concern in Canada and globally. Antibiotic use is a key driver of resistance, making it essential to understand how increased prescribing authority influences overall antibiotic use. At the same time, expanding pharmacists’ roles is intended to improve access to timely care for common, uncomplicated conditions and reduce pressure on physician offices and emergency departments.

This study helps answer a critical question: does allowing pharmacists to prescribe certain antibiotics lead to inappropriate or increased antibiotic use, or does it safely shift care, and antibiotic prescribing, for these conditions from physicians to pharmacists?

What were the key findings?
As expected, pharmacist prescribing increased for antibiotics that fall within the new policy. Between 2023 and 2024, Ontario pharmacists submitted more than 1.47 million minor ailment claims, with over one‑third related to uncomplicated UTIs and a smaller proportion related to Lyme disease prophylaxis.

For uncomplicated UTIs, pharmacist prescribing of eligible antibiotics, increased among women, the population eligible under the policy. At the same time, physician prescribing for these same antibiotics declined. Overall, there was a small increase in first-line UTI antibiotic prescriptions. After the program was implemented, physicians prescribed fewer broad‑spectrum antibiotics (Ciprofloxacin), and pharmacists increasingly recommended more appropriate first‑line options for treating UTIs (such as nitrofurantoin). This suggests that pharmacists are mostly replacing prescriptions that doctors were writing.

A similar shift was seen for doxycycline, which pharmacists are authorized to prescribe for Lyme disease prophylaxis. Pharmacist prescribing increased following the policy change, but this was offset by reduced physician prescribing, resulting in no overall change.

What about total antibiotic use?
When looking at all oral antibiotics, total community prescribing increased over the study period. However, this rise was driven by physician prescribing of other antibiotics unrelated to the minor ailments policy and reflects a return to pre‑pandemic prescribing patterns rather than an unintended consequence of expanded pharmacist scope.

Is there evidence that prescribing is staying within policy limits?
The data suggest pharmacists are prescribing in alignment with policy requirements and for the intended patient population. Prescribing rates for antibiotics outside of the minor ailments policy remained low; this is expected and related to pharmacists’ authority to adapt or renew prescriptions.

Pharmacist assessments often resulted in a prescription, but not always, demonstrating that pharmacists are referring when the patient presentation was beyond their scope of practice.

What does this mean for antimicrobial stewardship?
These findings indicate that pharmacist antibiotic prescribing in Ontario has not led to widespread overprescribing or inappropriate use for the conditions studied. Instead, the policy appears to be supporting a shift in care that increased recommended antibiotics for uncomplicated UTIs and Lyme disease prophylaxis while improving access to care.

The authors do emphasize that continued vigilance is necessary. As pharmacists gain additional prescribing authority, ongoing monitoring, surveillance, and support will be critical. This includes clear scope limitations, evidence‑based clinical guidance, and continuing education focused on antimicrobial stewardship.

What lies ahead?
Expanding pharmacist prescribing represents a significant evolution in how care is delivered in Ontario. The scope of practice has continued to evolve, expanding in October 2023 to include prescribing for six additional ailments. In September 2025, the Ministry of Health announced further plans to improve access to care, by proposing changes to enable pharmacists to assess and prescribe for an additional 14 ailments. This study underscores the importance of pairing scope expansion with robust monitoring to ensure patient safety and responsible antibiotic use.

Future research will be crucial to better understand prescribing appropriateness, treatment durations, and patient outcomes, as well as the broader health system impacts of pharmacist‑led care. Together, these efforts can help ensure that expanded access translates into high‑quality, sustainable care, while protecting the effectiveness of antibiotics for the future.

PHO promotes and supports antimicrobial stewardship to improve and optimize antimicrobial therapy and clinical outcomes for patients across all healthcare settings and in the community. Visit, PHO’s Antimicrobial Stewardship in Primary Care webpage, to explore more resources.