Risk factors for adverse drug reactions in patients admitted to intensive care units

Background: Patients hospitalized in intensive care units (ICU) are at higher risk of having adverse drug reactions (ADR). Aim: To determine risk factors for ADR, through intensive pharmacological surveillance at the ICU. Patients and Methods: An observational, descriptive and prospective study was made, determining risk parameters in patients who experienced ADR. Results: Eighty-five patients were surveilled and 24 (28%) had an ADR. A total of 48 drugs responsible for at least one ADR were identified. Seventy-three percent ADR were moderate and 27% were severe. The clinical variables significantly associated with ADR were a history of allergies, a high body mass index, the reason for admission, an APACHE II score >= 14 points, the use of invasive mechanical ventilation and more than seven days of hospitalization. The pharmacological variables associated with ADR were polypharmacy and medication associations and combinations. Conclusions: The identified risk factors have a great impact on pharmacokinetic and pharmacodynamic parameters, and should be considered to avoid the appearance of ADR.