Efficacy and safety of discontinuing antibiotic treatment for uncomplicated respiratory tract infections when deemed unnecessary. A multicentre, randomized clinical trial in primary care.

Objectives: To determine the benefits and harms of discontinuing unnecessary antibiotic therapy for uncomplicated respiratory tract infections (RTI) when antibiotics are considered no longer necessary.

Methods: Multicentre, open-label, randomized controlled clinical trial in primary care centres from 2017 to 2020 (ClinicalTrials.gov, NCT02900820). Adults with RTIs-acute rhinosinusitis, sore throat, influenza or acute bronchitis-who had previously taken any dose of antibiotic for less than 3 days, which physicians no longer deemed necessary were recruited. The patients were randomly assigned in a 1:1 ratio to discontinuing antibiotic therapy or the usual strategy of continuing antibiotic treatment. The primary outcome was the duration of severe symptoms (number of days scoring 5 or 6 on a six-item Likert scale). Secondary outcomes included days with symptoms, moderate symptoms (scores of 3 or 4), antibiotics taken, adverse events, patient satisfaction and complications within the first 3 months.

Results: A total of 467 patients were randomized, out of which 409 were considered valid for the analysis. The mean (SD) duration of severe symptoms was 3.0 (1.5) days for the patients assigned to discontinuation and 2.8 (1.3) days for those allocated to the control group (mean difference 0.2 days; 95% CI -0.1 to 0.4 days). Patients randomized to the discontinuation group used fewer antibiotics after the baseline visit (52/207 (25.1%) versus 182/202 (90.1%); p 0.001). Patients assigned to antibiotic continuation presented a relative risk of adverse events of 1.47 (95% CI 0.80-2.71), but the need for further health-care contact in the following 3 months was slightly lower (RR 0.61; 95% CI 0.28-1.37).

Conclusions: Discontinuing antibiotic treatment for uncomplicated RTIs when clinicians consider it unnecessary is safe and notably reduces antibiotic consumption.