Background and importance Pharmacovigilance (PV) is a public health activity in which clinicians are legally and medically involved. Notification of adverse drug reactions (ADRs) is essential to ensure the safety of medications.

Aim and objectives To describe the ADRs notified to the Regional Centre of Pharmacovigilance (RPC).

Material and methods A retrospective study was conducted between January 1992 and December 2018. The hospital pharmacist (HP) was responsible for data collection and notification. PV started up in 1992 accompanied by a strong information and communication campaign. Data were recorded and analysed in Excel 2007: sex and age of patients, total number of reported ADR notifications, detection method, severity and outcome of the ADRs, medications involved and therapeutic group (ATC classification).

Results During the 27 years of the study period, 1246 ADRs were reported (annual average: 46±2.83): 53.6% of patients were men and 54.2% were >65 years old while 10.6% were <30 years old. Regarding the detection method, 59.7% came from the minimum database set for hospital (MDS-H), 34.3% by voluntary notification of health staff and the remaining (6%) were detected by the HP during treatment validation. Mild ADRs accounted for 16.8%, 45% were moderate and the rest were severe. The outcome of the ADRs reported was recovered without sequelae in 92.8% of cases; 14 patients died (1.1%). A total of 1353 drugs were involved (median 42 per year (IQR 33–76.3)). The major therapeutic groups were N (nervous system) with 20.2% and M (musculoskeletal system) 19.6%, followed by C (cardiovascular system) 16.6% and J (anti-infectives for systemic use) 15.6%.

In 1992, 19 ADRs were notified, a value that progressively increased over the years, reaching its highest in 2003 (84 ADRs). In 2004 it decreased to 46, remained constant (mean 35.7±9.7) and then declined to 31 in the last year.

Conclusion and relevance More than one-third of ADRs were serious, but most patients recovered without sequelae. Most notifications to the RPC come from the MDS-H, but a significant number were detected by health staff and HP. In recent years, reported ADRs has decreased, so the HP could be an essential element to develop the pharmacovigilance programme, which is key to improving the safety of medicines by promoting relevant modifications in the technical data sheets and issuing alerts from the Spanish Agency for Medicines and Health Products.

References and/or acknowledgements No conflict of interest.