Adherence to Antibiotic Treatments in Community Pharmacy: Analysis by Therapeutic Groups and Associated Factors

Introduction: Non-adherence to antibiotic treatments contributes to the development of resistance. Community pharmacies provide an opportunity to assess and improve therapeutic adherence. This study analyzes which antibiotic groups present the highest non-adherence rates. Objective: To identify the therapeutic groups of antibiotics with the highest non-adherence in community pharmacy and to analyze associated factors such as age, sex, and reasons for treatment discontinuation. Methods: An observational, descriptive, and prospective study was conducted over 12 months in two pharmacies in a coastal town in Murcia, Spain. A total of 500 patients receiving antibiotic treatment were included. Sociodemographic variables and treatment characteristics were recorded. After 15 days, adherence was assessed using the Morisky-Green-Levine test, and reasons for non-adherence were documented. Chi-square statistical analysis and relative risks (RR) were calculated. Results: Of the 363 patients who completed the study, 37.2% did not adhere to their treatment. The highest non-adherence rates for oral treatments were observed in penicillin combinations with beta-lactamase inhibitors (52.4%) and extended-spectrum penicillins (46.8%). The most frequent reason was forgetfulness, followed by schedule changes and perceived clinical improvement. No significant differences were found by sex (p = 0.136) or age group (p = 0.209). The RR was higher for penicillin combinations (RR = 1.40; 95% CI: 1.10-1.78) and lower for macrolides (RR = 0.43; 95% CI: 0.23-0.79). Conclusions: Penicillins, especially combinations with beta-lactamase inhibitors, and topical antibiotics present a higher risk of non-adherence. Interventions from primary care and particularly from community pharmacy should be reinforced to improve adherence, especially in these groups.