The stability of ondansetron and fluconazole in 5% dextrose injection and normal saline during simulated Y-site injection at room temperature was studied. Ondansetron 0.03, 0.1 and 0.3 mg/ml were admixed 1:1 with fluconazole 2 mg/ml. The solutions were stored at room temperature and samples were retrieved at time 0, 1, 2, 4 and 12 hr for immediate assay. At the time of the assay and before any dilution, each sample was visually inspected for clarity, color, precipitation, and the pH was determined. Drug concentrations were measured by a stability-indicating high performance liquid chromatograph. Ondansetron 0.03, 0.1 and 0.3 mg/ml were stable when mixed with concentration of fluconazole 2 mg/ml. There were no change in clarity and color and no precipitates in any admixture for 12 hr of inspection. The pH measurements did not have a particular trend in any direction over time.