Objectives: Data of Literature suggest that age is not an independent risk factor for adverse drug reactions (ADR), while there is evidence of a positive correlation between ADR and the number of drug taken. To investigate if that is true, we have examined the occurrence of ADR in elderly patients admitted to our Geriatric Department in the first nine months of 1999 for acute illness.
Materials and methods: We have evaluated the occurrence of ADR in 510 patients more than 65 years of age (80 +/- 7.35 years). The adverse drug effect was worth considering when symptomatical or caused a change in the management of the patient (suspension or change of therapy, prolongation of staying in hospital). We used the algorithm of Naranjo (19) to estimate the probability that a drug caused an ADR.
Results and conclusions: In our study the frequency of ADR was 12.5%. Furosemide was responsible for 50% and digoxin for 8% of ADR. Among the patients taking furosemide, 12.5% had an ADR (generally low potassium). The frequency of ADR was correlated neither with the age of the subjects nor with the number of drug taken. It can be possible that the main cause of ADR is the type of drugs assumed by elderly.