How long can a PROZINC vial be used after it is opened?
Although product literature or labels for other insulin products advocate replacing insulin vials every month, there are no special requirements to periodically replace PROZINC once the bottle has been punctured under normal use conditions. PROZINC is a suspension and once mixed has a whitish cloudy appearance. Of course, if discoloration or other abnormal appearances are observed, indicating contamination within the vial, it should be discarded.
