Should you wipe the vial stopper every time?

Yes. Wipe the rubber top before inserting a needle, every entry, including on a multi-use vial you opened yesterday. Site and vial care is one of the topics the insulin injection consensus covers directly. Wiping once at first opening is a hygiene myth, not a measured shortcut. Repeated punctures can also shear tiny rubber fragments into the solution, a risk that is lower with a fine insulin needle than with a large one but not zero. This is not a dose or a protocol. Full walkthrough at /injecting.

Full injecting guide: sites, needles, rotation, safety

Educational use only. This database summarizes published research and is not medical advice. Where a dose appears it is a record of what a trial or clinic ran, or what people describe doing, with its source attached. Nothing here is a recommendation for personal use.

Part of injecting: sites, needles and safety. Subcutaneous vs intramuscular, site rotation, lipohypertrophy, needle length and gauge, vial hygiene at injection time, travel syringes, scar tissue, and when to stop and see a clinician. Full walkthrough at /injecting.