Predictors of Adverse Drug Reactions to Reserve Antibiotics in Hospitalized Patients: A Tertiary Care Study

Reserve antibiotics are frequently used in hospitalized patients with severe infections, particularly in tertiary healthcare institutions. Although these agents are essential for the treatment of multidrug-resistant infections, their use may be associated with an increased risk of adverse drug reactions(ADRs). Identification of clinical and laboratory predictors of ADRs may contribute to safer and more rational antibiotic therapy. To determine the frequency of ADRs during treatment with reserve antibiotics in hospitalized patients at the University Clinical Center Kragujevac (UCCKg) and to identify factors associated with their occurrence. This observational study had a prospective–retrospective design and included spontaneous reporting of ADRs to reserve antibiotics by clinical pharmacologists during regular consultations with patients receiving these drugs. The study was conducted in all units of the UCCKg among patients for whom a consultation with a clinical pharmacologist had been requested by the attending physician between January 2022 and December 2023. Data were collected from the consultation registry archive and the electronic health information system of the UCCKg. Among patients receiving reserve antibiotics who were consulted by clinical pharmacologist, 52 developed ADRs. Significant factors associated with their occurrence were chronic renal insufficiency(adjusted OR 3.36), heart failure(adjusted OR 0.26), and peptic ulcer disease(adjusted OR 0.27). Reserve antibiotics are essential in the treatment of severe infections and are frequently used in tertiary healthcare institutions. Their use is associated with a certain incidence of ADRs, particularly in patients with renal failure or prolonged severe infections. These factors should be considered during treatment planning to prevent unfavorable outcomes.