Adverse drug reaction monitoring: support for pharmacovigilance at a tertiary care hospital in Northern Brazil.

Background: Adverse drug reactions (ADRs) are recognised as a common cause of hospital admissions, and they constitute a significant economic burden for hospitals. Hospital-based ADR monitoring and reporting programmes aim to identify and quantify the risks associated with the use of drugs provided in a hospital setting. This information may be useful for identifying and minimising preventable ADRs and may enhance the ability of prescribers to manage ADRs more effectively. The main objectives of this study were to evaluate ADRs that occurred during inpatient stays at the Hospital Geral de Palmas (HGP) in Tocantins, Brazil, and to facilitate the development of a pharmacovigilance service.

Methods: A prospective study was conducted at HGP over a period of 8 months, from January 2009 to August 2009. This observational, cross-sectional, descriptive study was based on an analysis of medical records. Several parameters were utilised in the data evaluation, including patient demographics, drug and reaction characteristics, and reaction outcomes. The reaction severity and predisposing factors were also assessed.

Results: The overall incidence of ADRs in the patient population was 3.1%, and gender was not found to be a risk factor. The highest ADR rate (75.8%) was found in the adult age group 15 to 50 years, and the lowest ADR rate was found in children aged 3 to 13 years (7.4%). Because of the high frequency of ADRs in orthopaedic (25%), general medicine (22%), and oncology (16%) patients, improved control of the drugs used in these specialties is required. Additionally, the nurse team (52.7%) registered the most ADRs in medical records, most likely due to the job responsibilities of nurses. As expected, the most noticeable ADRs occurred in skin tissues, with such ADRs are more obvious to medical staff, with rashes being the most common reactions. Metamizole, tramadol, and vancomycin were responsible for 21, 11.6, and 8.4% of ADRs, respectively. The majority of ADRs had moderate severity (58.9%), thus requiring intervention. Type A reactions were the most common (82.1%). At least one predisposing factor was present in 79.9% of the reports examined, and the most common predisposing factor was polypharmacy.

Conclusions: The results obtained will contribute to the development of strategies for the pharmacovigilance service at HGP and other hospitals throughout the country, which will improve the quality of ADR reporting and ensure safer drug use in Brazilian hospitals.