Multicenter evaluation of ondansetron use in hospitalized oncology patients.

An evaluation of ondansetron use in oncology patients in three hospitals is described. Criteria for the use of ondansetron were developed and approved by each hospital's pharmacy and therapeutics committee or medical staff executive committee. Ondansetron use was concurrently monitored in adult inpatients for four months. Nursing and physician notes were reviewed, and the patients were interviewed. Data were collected on patient demographics, medical history, dosage of ondansetron, outcome, adverse effects, and concurrent medications. The approved criteria were used to evaluate the appropriateness, effectiveness, and safety of ondansetron therapy. A total of 262 oncology patients were evaluated. Of these, 223 (85%) received ondansetron appropriately based on the emetic potential of their antineoplastic drug regimen. Ondansetron was correctly prescribed for acute-phase prophylaxis of nausea and vomiting in 252 patients (96%). Only 117 (45%) of the patients met the criterion for appropriate dosage. The mean +/- S.D. dose of ondansetron was 11.7 +/- 3.22 mg, and the mean +/- S.D. number of doses received per patient was 4.4 +/- 3.23. Of the 135 patients who received an inappropriate dosage, 106 (79%) were given a dose larger than currently recommended by the manufacturer. Positive outcomes, defined as no more than two episodes of vomiting, no more than two episodes of retching, and no more than two p.r.n. doses of antiemetics, were observed in 97%, 99.6%, and 94% of the 248 patients included in the outcome analysis, respectively. Chemotherapy was completed on schedule in all the patients, and there were no complications due to excessive vomiting or retching. Adverse reactions were reported by 21 patients (8%).(ABSTRACT TRUNCATED AT 250 WORDS)