[Analysis of adverse drug reactions detected in a primary health care center].

Objective: To determine the incidence and epidemiological characteristics of adverse drug reactions (ADR) and to assess their relevance in primary health care.
Design: An open prospective descriptive study.
Patients: All patients cared for in one primary health care centre during 2 months.
Measurements and Main Results: 73 ADR were detected during the period of study (two of which corresponded to pediatric patients) with an incidence of 1.35% in adult general medicine and 0.36% in pediatric medicine. 67% of the patients were female, and all adult patients were distributed into three age groups (15-44, 45-64 and > or = 65 years of age). The frequency of ADR was similar in all three age groups. The ADR were most present in the GI tract, central nervous system, general symptoms and skin. Among the most frequently pharmacological groups implicated in the ADR were cardiovascular drugs, antibiotics and drugs for the central nervous system. Only in 12 cases the ADR was considered as clinically relevant, according with the criteria of the participating physicians; in 6 cases they were evaluated as avoidable.
Conclusions: The ADR are not a relevant clinical problem, nor are they frequent in the outpatients primary health care. In most cases there are slight and self-limiting, which appeared in a limited number of patients. However clinically relevant and important ADRs appeared in 0.1-0.3% of the consultations, which, in practice, represent one to two serious ADRs per month and physician.