The data behind zoledronic acid being superior to other agents like pamidronate is a little questionable. (1) The infusion time as a convenience issue is likely irrelevant for anyone sick enough to require admission (2) These agents take days to work! In the primary study comparing the two (J Clin Oncol 2001;19:558-67) there was no statistically significant difference in the percentage of complete responders at 4 days (their first measured timepoint) between the pamidronate group and the zoledronic acid 4 mg group; the difference was shown with the zoledronic acid 8 mg dose, which is not what is currently approved/recommended in the US. For outpatient chemo infusion centers, therapy with zoledronic acid makes sense because the infusion time can be much more convenient. However, in the ED this is not likely to make as much of a difference. I’m still pretty comfortable recommending pamidronate in the ED for this indication, and we’ve restricted zoledronic acid to outpatient/infusion clinic use only.