Reduced renal function requires dose adjustment for certain drugs to avoid toxicity. The aim of this study was to determine whether appropriate dosage adjustments were made for drugs that are nephrotoxic, excreted, or metabolized (TEM medications) by the kidney in patients with renal impairment.

A cross-sectional study of a group of hospitalized patients was carried out at Al-Watni governmental hospital, Nablus, Palestine. All patients with creatinine clearance ≤59 ml/min were included in the analysis. Data regarding patients' clinical, laboratory findings and medications whether they were prescribed at hospital or at discharge were collected from patients' medical files. Evaluation of appropriate dosing was based on Physician Disk Reference (PDR). All data were collected for further research and subsequent statistical analysis using statistical package for social sciences (SPSS) for windows version 10.

A total of 78 patients had calculated creatinine clearance ≤59 ml/min. Those patients were prescribed a total of 1001 lines of prescription medication. Dosage adjustment was necessary for 193 TEM medications. Analysis of TEM medications with guidelines for adjustment indicated that 73.58%(142) were found to be inappropriate and 26.42% (51) were found to be appropriate. The most common inappropriate medications were ranitidine, antibiotics, and digoxin. Approximately 77.5% of the unadjusted medications were prescribed during hospitalization.

In our study, a wide range of dosing errors was common among patients with renal impairment that was common during hospitalization. Continued medical education in the field of clinical pharmacokinetics is important for physicians. Copyright © 2007 John Wiley & Sons, Ltd.