Difficulty breathing; Got hot/ was hot; Flushed; Electrical impulses at the bottom of sphine, lower back; Was in pain and could not sit properly as a consequence/ achy all over; Trouble walking/ was given shopping cart so she could support herself going to her car; Flu like symptoms/ was walking around like I had the flu; Muscles got weak and the patient felt like she could not stand; Elevated temperature (99F); Feeling very peculiar; This spontaneous case from  was received on 02-Nov-2022 from other non-healthcare professional (consumer) via Agency (reference number: SEQW22-05325), with additional information received on the same date and on 03-Nov-2022 (being processed together) and concerned a 76-year-old, female patient.  The patient's medical history was not reported. The patient's past procedures included replacement of both knees (the patient had been on physical therapy). The patient's concomitant medications included lisinopril and meloxicam, both used for unreported indications. The patient's historical vaccines included Fluzone (influenza vaccine), received on an unspecified date in 2021, after which the patient experienced a normal sore arm, first and second booster doses of Covid-19 vaccine (brand not specified), received on an unspecified dates, after both of which the patient felt like having the flu for 24 hours, and third booster dose of Covid-19 vaccine, received on 06-Oct-2022.   On 28-Oct-2022, the patient was vaccinated with Fluad Quadrivalent (influenza vaccine inact sag 4v; dose: 0.5 ml, route of administration, anatomical location: not reported) for active immunization of persons 65 years of age and older against influenza caused by influenza virus subtypes A and B contained in the vaccine. The batch number was not reported.  On the same day, two minutes after receiving Fluad Quadrivalent, the patient started feeling very peculiar. The patient got hot, had a mask and had difficulty breathing, the muscles got weak and the patient felt like she could not stand. The patient went back to the pharmacy where she was told to sit down. The patient was flushed, was hot and started feeling electrical impulses at the bottom of spine, lower back, which lead to sort of leaning back in the chair since the patient was in pain and could not sit properly as a consequence. That feeling lasted two minutes. The patient then took a glass of water and was given a shopping cart so she could support herself going to the car. The patient was still flushed during the rest of the day, and started having flu-like symptoms. By evening, the patient had an elevated temperature (99 degrees of Fahrenheit (F)), and was walking around like she had the flu.  On the same date, the patient recovered from the event of 'electric shock sensation'.  On 29-Oct-2022, the patient recovered from the events of 'difficulty in standing', pain and 'walking difficulty'. As reported, the next day, at 4 pm, the patient started feeling better and was no longer achy all over nor did she continue to have trouble walking.  On an unspecified date in 2022, the patient took a plurality of Tylenol (paracetamol) pills as a treatment measures for event.  On an unspecified date in 2022, the patient recovered from all other events. The patient stated that the state she was in was transitory and had not had a reoccurrence of the symptoms.  The reporter assessed the events as related to Fluad Quadrivalent. The patient was surprised at her own reaction since she never previously had had one to a flu shot, apart form the arm soreness which the patient dismissed as normal).  The case was assessed as non-serious.  Company comment: A 76-year-old, female patient was vaccinated with Fluad Quadrivalent. Two minutes after vaccination, the patient started feeling very peculiar. In addition, the patient reported dyspnoea, feeling of hotness, flushing, electric shock sensation, pain, walking difficulties, flu like symptoms, muscular weakness and body temperature increased.  The patient's medical history was not reported. The patient's historical vaccines included Fluzone (influenza vaccine), after which the patient experienced a normal sore arm, first and second booster doses of Covid-19 vaccine after both of which the patient felt like having the flu for 24 hours, and third booster dose of Covid-19 vaccine. Information regarding relevant diagnostic findings was not provided. Causal role of the suspect vaccine cannot be excluded and is assessed as possibly related, with the currently available information and plausible temporal relationship.; Reporter's Comments: The patient stated that the state she was in was transitory and had not had a reoccurrence of the symptoms.; Sender's Comments: A 76-year-old, female patient was vaccinated with Fluad Quadrivalent. Two minutes after vaccination, the patient started feeling very peculiar. In addition, the patient reported dyspnoea, feeling of hotness, flushing, electric shock sensation, pain, walking difficulties, flu like symptoms, muscular weakness and body temperature increased.  The patient's medical history was not reported. The patient's historical vaccines included Fluzone (influenza vaccine), after which the patient experienced a normal sore arm, first and second booster doses of Covid-19 vaccine after both of which the patient felt like having the flu for 24 hours, and third booster dose of Covid-19 vaccine. Information regarding relevant diagnostic findings was not provided. Causal role of the suspect vaccine cannot be excluded and is assessed as possibly related, with the currently available information and plausible temporal relationship.