Preventability of Adverse Drug Reactions Related to Antibiotics: An Assessment Based on Spontaneous Reporting System

Antibiotics are commonly used in both outpatient and inpatient settings and are responsible for the majority of adverse drug reaction (ADR) reports. We aimed to characterize spontaneously reported ADRs associated with antibiotics and assessing the preventability of these ADRs in a Vietnamese setting.

We conducted a retrospective descriptive study based on ADRs related to antibiotics spontaneously reported by healthcare workers to the National Pharmacovigilance Database of Vietnam (NPDV) between June 2018 and May 2019. The characteristics of included reports were descriptively analyzed. The preventability of reported ADRs was assessed using a standardized preventability scale. We identified the leading causes and described the characteristics associated with preventable ADRs (pADRs).

We included 6385 antibiotic-related reports from a total of 12,056 reports submitted to the NPDV during the study period. Beta-lactam antibiotics, mostly broad-spectrum with parenteral route, were suspected in the majority cases. The most commonly reported pADRs were allergic reactions, mostly classified under skin and subcutaneous tissue disorders. Of all included cases, 537 cases (8.4%) were deemed as associated with pADRs. Major causes of pADRs include potentially inappropriate prescribing (352/537, 65.5%) and re-administration of antibiotics causing prior allergy/allergies (99/537, 18.4%). The majority of pADRs involved the use of beta-lactam antibiotics with inappropriate indications.

ADRs related to antibiotic use represent more than half of ADRs spontaneously reported in Vietnam. Approximately one in every ten reported cases is associated with pADRs. The majority pADRs can be prevented through simple improvement in antibiotic prescribing practices.