Analysis of prognostic factors for the antipyretic response to ibuprofen

AIM: To assess the factors influencing the antipyretic activity of ibuprofen in children. PATIENTS AND METHODS: Children aged between 1 and 10 years attending the emergency department with a temperature of> 38 degrees C were given one dose of ibuprofen (7 mg/kg). Temperature was recorded before and 30, 60, 90, 120, 180 and 240 min after ibuprofen administration. The influence of age, sex, weight, body surface, nosologic entity, previous antipyretic administration, and the association between physical measurements and temperature evolution were assessed. RESULTS: A total of 384 children were studied. Baseline temperatures were between 38 degrees C and 42 degrees C (mean: 39.1 +/- 60.6). Most of the patients (77.8%) had been feverish for more than 6 hours and 59.5% had received antipyretic treatment. In 93.5% of the children temperature was lowered to 37.5 degrees C or less. In 80.2% of the children this temperature was reached 12 hours after treatment. In 95% of ther children a decrease of at least 1 degree C was achieved. Older age (OR 1.67; 95% CI: 1.032.7), smaller body surface (OR 0.004; 95% CI 00.89) and lower baseline temperature (OR 0.008; 95%CI 00.14) were associated with a smaller antipyretic response (decrease in body temperature lower than 1 degree C). CONCLUSIONS: Ibuprofen is effective in the treatment of fever in children. Its effectiveness is related to age, the degree of fever and body surface.