Definition: A multi-dose vial holds more than one dose and is made to be entered more than once. CDC says that once opened, it should be dated and thrown away within 28 days unless the manufacturer states another date. The 10 mL Depo-Testosterone vial and compounded GLP-1 vials are common examples.
CDC defines a multi-dose vial as one that contains more than one dose and is approved for repeated use. Citing USP chapter 797, it says the vial should be dated when opened and discarded within 28 days unless the manufacturer states another date, and that a vial should be assigned to a single patient whenever possible.
For compounded GLP-1 vials, FDA says multi-dose vials of sterile medicine should be used within 28 days after first use, thrown away after that even if medicine is left, and entered with a new sterile needle and syringe for each dose.
The manufacturer's date can be different. The Lantus label, for example, says not to use an opened vial more than 28 days after first use, and some pens carry longer in-use limits.
How many weekly doses fit in 28 days
The clock starts at the first puncture, not the purchase date, so the open date is the one to write down. Dose Track saves each vial with its mix date and concentration, which keeps the open date next to the doses drawn from it.
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