confusion; lethargy; he received his first booster as an undiluted administration of the purple cap formulation, resulting in 6 doses instead of one; he received his first booster as an undiluted administration of the purple cap formulation, resulting in 6 doses instead of one; This is a spontaneous report received from contactable reporter(s) (Nurse) from medical information team, Program ID: (159558).  A 59-year-old male patient received BNT162b2 (BNT162B2), on 04Nov2021 as dose 3 (booster), single (Lot number: FD0809) at the age of 59 years for covid-19 immunisation. The patient's relevant medical history was not reported. Concomitant medication(s) included: INFLUENZA VACCINE, in Oct2021 as dose number unknown, single. Vaccination history included: Covid-19 vaccine (Dose 1, Manufacturer unknown), for Covid-19 immunization; Covid-19 vaccine (Dose 2, Manufacturer unknown), for Covid-19 immunization. The following information was reported: OVERDOSE (non-serious), PRODUCT PREPARATION ERROR (non-serious) all with onset 04Nov2021, outcome "unknown" and all described as "he received his first booster as an undiluted administration of the purple cap formulation, resulting in 6 doses instead of one"; CONFUSIONAL STATE (non-serious) with onset 05Nov2021, outcome "recovered", described as "confusion"; LETHARGY (non-serious) with onset 05Nov2021, outcome "recovered".  Additional Information: It was stated that reporter was reported that patient was asking for his second booster dose; however, he received his first booster as an undiluted administration of the purple cap formulation, resulting in 6 doses instead of one. Reporter was asking any information on that. Nurse on the line who is reporting that one of their staff received the Covid 19 booster dose purple cap that was undiluted. She mentioned the patient was a nurse staff in there facility and Caller wanted to know what is the possible side effects since incorrectly prepared. Asking should they re-administer the booster dose. Caller said she wasn't asking if she should re administered the booster dose. Caller said he took 6 doses, and she didn't give the dose of the purple cap undiluted and now patient was asking for another booster vaccine. Caller said she was not giving another booster dose without approval, and she said the pharmacist said no. Caller said she had already reported in VARES when the event happens. Caller said not really when asked to complete report and said she has been on hold for a while, and she has been transferred 4 times. Caller declined to complete report. HCP called earlier today and reported a Male, received a PBCV purple cap formula vaccine booster dose in Nov2021. When he received the booster dose, he received a full vial of the undiluted purple cap formulation, resulting in 6 doses instead of one. She had reviewed the information sent by previous Agent withheld and had questions regarding the information she received per email. She was asking about the guidelines stating. If the administration error resulted in a higher-than-authorized vaccine dose, in general the second dose may still be administered at the recommended interval. She believed this applies to the primary series and not specifically to the PBCV booster dose. Did the same information apply to the PBCV booster dose #2, which the patient was now due to receive. Did agency had any information about this. Booster dose was administered due to high risk of frequent institutional or occupational exposure to coronavirus (and at risk of serious COVID-19 complications). The patient was an RN and a supervisor at the facility who wanted a booster. The reporter had the day off and was not in the office. The RN came into the reporter's office and brought out a vial of undiluted vaccine and had an LPN give him the whole vial. She gave him the whole vial and did not dilute. They realized the error when they had to give another booster and did not have any vaccine in the vial left. They called the reporter at home, and she explained it needed to be diluted, and they should have had enough, and they reported the overdose error. The patient reported confusion and lethargy the day after the overdose event. He missed work because of the adverse events. They have resolved, but the reporter did not know when, as the overdose event was some time ago.