Trends in primary care antibiotic prescribing during the implementation of national stewardship policies: Türkiye, 2011-2019.

Background: Antimicrobial resistance is driven by inappropriate antibiotic use, and Türkiye has long shown one of the highest outpatient consumption rates in the WHO European Region. In response, the Ministry of Health implemented stewardship measures from 2014 onward, including the National Action Plan for Rational Drug Use, banning over-the-counter antibiotic sales, integrating e-prescribing with mandatory diagnostic coding, educational initiatives, and audit-feedback systems. This study evaluated temporal trends in primary care antibiotic prescribing in Türkiye between 2011 and 2019 and assessed the influence of these interventions. Methods: We performed a nationwide descriptive analysis using aggregated Prescription Information System (RBS) data covering all family-physician prescriptions (2011-2019). Outcomes included: (i) proportion of prescriptions containing systemic antibiotics (ATC J01), (ii) consumption in DID, (iii) use by ATC-3 class and AWaRe category, (iv) antibiotic share of drug volume and cost, and (v) patterns by age, sex, and diagnosis. Trends were summarized using annual percentages and DID values. The two pre-specified primary outcomes were the annual antibiotic prescription rate and total systemic antibiotic consumption (DID, ATC J01); other indicators were treated as secondary. Because the RBS captures only e-prescribed antibiotics, over-the-counter sales (legal in Türkiye until 2016) are not included. Segmented (interrupted time-series) regression with Newey-West HAC standard errors was applied to test for changes in level and slope at 2016, when prescription-only dispensing was fully enforced and mandatory ICD-10 coding was consolidated within the e-prescribing system. Results: Among 1.17 billion prescriptions, the share containing an antibiotic declined from 34.9 to 23.9%, while consumption fell from 42.3 to 31.9 DID (-25%). Beta-lactams showed the largest reductions, though Watch-group agents still formed nearly half of use in 2019, below the WHO ≥60% Access target. Pediatric prescribing decreased most: use in children aged 0-6 years dropped from 60 to 44% of visits. Elderly patients had the lowest rates. Diagnostic coding shifted away from nonspecific upper-respiratory infections. Antibiotics' share of outpatient drug costs fell from 10.7 to 4.7%, yielding an estimated 1.7 billion TL savings in 2018. Segmented regression confirmed an acceleration of the decline after 2016: the slope changed by -0.69 percentage points/year for the prescription rate (95% CI - 1.44 to +0.06; Conclusion: Türkiye achieved major reductions in primary care antibiotic use within a decade, temporally concordant with multifaceted stewardship policies whose individual contributions cannot be isolated by this descriptive design. However, outpatient levels remain above many EU countries, and Watch-group use is still high. Further progress requires stronger guideline adherence, prioritization of Access antibiotics, and wider use of point-of-care diagnostics.