Abstract
Adverse drug reaction (ADR) severity levels are mainly rated by healthcare professionals (HCPs), but patient ratings are limited. This study aimed to compare patient-rated and pharmacist-rated ADR severity levels and determined methods employed for ADR management and prevention by patients and HCPs. A cross-sectional survey was conducted in outpatients visiting two hospitals. Patients were asked about ADR experiences using a self-administered questionnaire, and additional information was retrieved from the medical records. In total, 617 out of 5594 patients had experienced ADRs (11.0%), but 419 patients were valid (68.0%). Patients commonly reported that their ADR severity level was moderate (39.4%), whereas pharmacists rated the ADRs as mild (52.5%). There was little agreement between patient-rated and pharmacist-rated ADR severity levels (κ = 0.144; p < 0.001). The major method of ADR management by physicians was drug withdrawal (84.7%), while for patients, it was physician consultation (67.5%). The main methods for ADR prevention by patients and HCPs were carrying an allergy card (37.2%) and recording drug allergy history (51.1%), respectively. A higher level of ADR bothersomeness was associated with higher ADR severity levels (p < 0.001). Patients and HCPs rated ADR severity and used ADR management and prevention methods differently. However, patient rating of ADR severity is a potential signal for severe ADR detection of HCPs.