It appears that when prescribing meds in powder or liquid form, the volumes (i.e. mls or grms) that appear in the drop-down menu do not accurately represent that which is available. As a result, the e-prescribing module rejects the Rx and we have to find out the precise available package. Would be nice if the med database included the specific commonly-available sizes/volumes of the meds, rather than just the generic 40, 50, 100, 250, etc.