broke out in hives afterwards; Initial information received on 14-Nov-2023 regarding an unsolicited valid  non-serious case received from a consumer/non-hcp (Non-healthcare professional).  This case is linked to case 2023SA358226(CLUSTER).  This case involves a 80 years old female patient who broke out in hives afterwards receiving vaccine Influenza Quadrival A-B High Dose Hv Vaccine [Fluzone High-Dose Quadrivalent].  The patient's past medical history, medical treatment(s), vaccination(s) and family history were not provided. At the time of the event, the patient had ongoing Mycotic allergy and Allergy to animal.   On 22-Oct-2023, the patient received an unknown dose of suspect Influenza Quadrival A-B High Dose Hv Vaccine (Strength: Standard) (Frequency: once) (with an unknown strength, formulation, expiry date, lot number) via unknown route in the left arm for immunization.  On 23-Oct-2023, the patient broke out in hives afterwards (urticaria) (latency: 1 day).  It was reported, The patient reports that she had an allergic reaction to FLUZONE HD QIV. She states that she has received FLUZONE HD QIV in previous years and never experienced an adverse reaction; she asks if anything in the FLUZONE HD QIV ingredients has changed! Her allergist recommended that she receive half the FLUZONE HD QIV at at time in the future; she asks if they can do that! The patient states that in previous years she received FLUZONE HD QIV, but this year she received it at the doctor's office, she asks if that would make any difference! MIS explained that this should not affect the ingredients in the FLUZONE HD QIV. The patient asks what she should do about her flu shot next year! MIS explained that severe allergic reaction is a contraindication to receiving FLUZONE HD QIV and referred the patient to her healthcare provider.This is reported to PV as an SAE due to an 80-year old female patient reports that she received FLUZONE HD QIV at the doctor's office on 22Oct2023; reports that she broke out in hives afterwards, so she went to the walk-in clinic and was prescribed steroids and Benadryl. She reports that shortly after that, her tongue started swelling and her throat started feeling awful; her daughter called 911 and she was transported to the emergency department on 23Oct2023. She reports that she was in the emergency department for 2 to 3 hours and received medications through an IV; it is unknown to the reporter what medications she received via IV. She reports that after 2-3 hours, she felt fine and so they sent her home from the emergency department. The patient confirms that all her symptoms have resolved at the time of this call. The patient also notes that after this occurred, she was referred to an allergies and they did allergy testing. She states that they found that she was allergic to tree mold, cats, and dogs; confirms that she was not found to be allergic to eggs or any other foods.   Action taken: not applicable.  The patient was treated with Diphenhydramine Hydrochloride (Benadryl [Diphenhydramine Hydrochloride]) for Urticaria.  At time of reporting, the outcome was Recovered / Resolved on an unknown date for the event broke out in hives afterwards.