Upon internal review, significant correction done on 10 Oct 2016 to update case validity and seriousness of event wrong drug administered. Initial unsolicited misuse report received from the literature on 27-Sep-2016. This case is linked to 2016SA181196, 2016SA181233, 2016SA181234, 2016SA181235, 2016SA181236, 2016SA181237, 2016SA181238, 2016SA181239, 2016SA181241, 2016SA181242, 2016SA181243, 2016SA181244, 2016SA181245, 2016SA181246, 2016SA181247, 2016SA181248, 2016SA181249, 2016SA181250, 2016SA181251, 2016SA181252, 2016SA181260. (same literature article). The following is verbatim from the article: Introduction there have been isolated case reports of medication product mix-ups involving insulin unintentionally given to patients when the intent was to administer vaccines. Information on how and why these types of errors occur is limited. Objective To describe incidents of unintentional administration of insulin instead of influenza vaccine and identify possible causes for errors. Methods we describe a 2014 investigation of an apparent mix-up where a cluster of five adult patients unintentionally received insulin instead of influenza vaccine. We also searched Centers for Disease Control and Prevention (CDC) and US Food and Drug Administration (FDA) vaccine and drug safety monitoring databases from January 2005 to April 2015 in order to identify other incidents. We classified cases as either 'highly suggestive' or 'suggestive' of insulin and influenza vaccine mix-ups. Results Investigation of the primary cluster incident revealed deviations from recommended practices for storage, handling, preparation, and administration of drugs and vaccines; the five cases were classified as highly suggestive of insulin and influenza vaccine mix-ups. Our search of CDC and FDA vaccine and drug safety monitoring databases identified an additional two highly suggestive and 15 suggestive cases, for a total of 22 cases (7 highly suggestive and 15 suggestive) during the 10-year study period. Conclusion Insulin and vaccine mix-ups have the potential to cause serious harm to patients, and are preventable with proper training and application of standards. Our investigation indicated that improper storage including inadequate segregation of insulin and influenza vaccine products in clearly labeled containers or bins lack of standardized procedures for confirming the contents of vials, and decreased vigilance in preparation and administration likely contributed to the primary cluster incident. This case involves a 79-year-old female patient who was administered injection of Insulin (insulin NOS) (manufacturer: other batch number, expiry date, route and site of administration: not reported) instead of receiving a dose of seasonal trivalent inactivated influenza vaccine (manufacturer: unknown) on an unspecified date in 2008. Patient had history of diabetes and was taking metformin hydrochloride (concomitant medication). On an unspecified date in 2008, post administration of insulin, the patient experienced weakness, sweating, seizure activity and drooling and hypoglycemia was described. It was a case of wrong drug administered (unintentional administration of insulin instead of influenza). Patient was seen in emergency room. No laboratory value was reported (for hypoglycemia). Corrective treatment was not reported. On an unspecified date, patient recovered from the events. Upon internal review, the case was considered as serious due to important medical events unintentional administration of insulin instead of influenza and hypoglycemia described, but no laboratory value provided. List of documents held by sender: none. Addendum: 10 Oct 2016. Upon second medical examination of case at time of internal review the following has been modified in this case: Validity of case (case became valid) and seriousness of event wrong drug administered (event became non serious). Sender's Comments: This case corresponds to a poorly documented literature case with mention of unintentional administration of insulin instead of influenza vaccine. The reported events are consistent with signs of severe hypoglycemia secondary to accidental insulin administration, however influenza vaccine was not administered in this case.