Study of drug dose calculation for morbidly obese patients

The objective of this study is to analyse the appropriateness and characteristics of drug dose calculation for hospitalised, morbidly obese patients. Retrospective, descriptive study of dose calculations for drugs prescribed to hospitalised, morbidly obese patients in a tertiary hospital in 2007. The recommendations prepared by the Pharmacy division are used as a standard. We included 62 patients. The mean number of medications prescribed per patient was 12.1 (4-39), and an average of 2.4 (1-10) are listed in the recommendations. A total of 135 drugs were prescribed. Dose calculations for 81 of the above (60 %) coincided with recommendations and 54 (40 %) did not; there were 51 cases of underdosing and three cases of overdosing. Improper dosing was detected for prescriptions in the systemic antibiotic and antithrombin drug groups, with underdosing being more common than overdosing.