Gave undiluted childrens BioNTech Pfizer Covid 19 Vaccine to adult; Gave undiluted childrens BioNTech Pfizer Covid 19 Vaccine to adult; Gave undiluted childrens BioNTech Pfizer Covid 19 Vaccine to adult; elevated temperature; fatigue; This is a spontaneous report received from a contactable reporter(s) (Pharmacist) from medical information team, Program ID.  A 66-year-old female patient received BNT162b2, BNT162b2 omi ba.4-5 (BNT162B2, BNT162B2 OMI BA.4-5), on 21Jul2023 at 13:45 as dose number unknown (orange cap; booster), 0.3 ml single (Lot number: GK0876, Expiration Date: 31Aug2024) at the age of 66 years, in left deltoid for covid-19 immunisation. The patient had no relevant medical history. There were no concomitant medications. Vaccination history included: BNT162b2, BNT162b2 omi ba.4-5 (DOSE NUMBER UNKNOWN (BOOSTER), SINGLE, lot number: GJ5342, expiry date: 30Jun2023), administration date: 29Sep2022, when the patient was 66-year-old, for COVID-19 immunization, reaction(s): "it was fine at the time"; Covid-19 vaccine (Primary Immunization series complete; unknown manufacturer), for COVID-19 immunization. The following information was reported: PRODUCT ADMINISTERED TO PATIENT OF INAPPROPRIATE AGE (non-serious), PRODUCT PREPARATION ERROR (non-serious), OVERDOSE (non-serious) all with onset 21Jul2023, outcome "unknown" and all described as "Gave undiluted childrens BioNTech Pfizer Covid 19 Vaccine to adult"; BODY TEMPERATURE INCREASED (non-serious) with onset 21Jul2023, outcome "unknown", described as "elevated temperature"; FATIGUE (non-serious) with onset 21Jul2023, outcome "unknown". Relevant laboratory tests and procedures are available in the appropriate section.  Additional information: Updated Information Included: Reporter information [Mailing address. Institution name]. patient information. Historical vaccine. Lab test. Dose information [Dose administration date/time. Dose unit. Lot number. Expiration date. Anatomical location]. Vaccine Facility information. Event onset date. Pharmacist reported that they administered an undiluted bivalent Pfizer covid vaccine for the age 5-11 formulation to an adult patient. It is probably between not significant and maybe medically relevant for if the patient has some fatigue or elevated temperature but he would say not significant in his opinion; caller was asked to clarify and states for the patient having some fatigue or elevated temperature, this happened about 30 minutes ago so the patient has probably not had that happen and based on the information the previous agent gave him it looks like no severe reaction has occurred for the event at a double dose being administered. Due to caller clarified in his opinion the event is not significant, this report is filed as not serious for seriousness criteria. He did the math and it comes out to like 42mcg of active ingredient of the dose administered and he is assuming there is 0.7ml in the saline of the vaccine. This dose was administered at 1:45pm. For this dose of the Pfizer bivalent covid vaccine, it looks like is that right for NDC for the bivalent and the NDC is 592670565 and ends in 02 for the box but the vial has NDC 592670565 and ends in 01 for the unit dose on it.