A tightness in the chest; Blood pressure had spiked to 187/102/blood pressure was 217/110; Headache; Not feeling well; Her head starting bob up and down indicating she was about to pass out, which she did; Little lightheaded; Blood pressure had dropped to 88/90; Heart rate was to 108 bpm; Flu symptoms; Fever; This spontaneous case was received on 16-Nov-2021 from other non-healthcare professional (patient's husband) via regulatory authority (reference number: SEQW21-05418) and concerned a female patient of an unreported age.  The patient's medical history and concomitant medications were not reported.  On 09-Nov-2021, the patient was vaccinated with Fluad Quadrivalent (influenza vaccine, inactivated influenza virus surface antigen (subunit), egg-derived, mf59; dose, route of administration, anatomical location and indication: not reported). The batch number reported was 312879 and expiry date was reported as 30-Jun-2022.  On 10-Nov-2021, one day after receiving Fluad Quadrivalent, the patient experienced a fever and mild flu symptoms. Later, the patient's temperature reached 102 (units not provided), and she took a dose of acetaminophen. Temperature dropped to 99.1 where it remained throughout the following night.  On 11-Nov-2021, two days after receiving Fluad Quadrivalent, the patient was not feeling well and was little lightheaded. The patient's husband measured her temperature and it was 99.8, her blood pressure was 108/92 and hearth rate was to 108 bpm. While sitting at the kitchen table, the patient's husband noted that her head started bob up and down indication that she was about to pass out, which she did, and he lowered her to the floor. The patient regained consciousness within a few seconds of being lowered on the floor. Since the pressure cuff was still on her arm, the husband measured her blood pressure again and found it had dropped to 88/90 and heart rate was 104. The patient took saltine cracks to help stimulate an increase in blood pressure and she seemed to improve. Within an hour her blood pressure was stabilized at 125/92 and heart rate was 94.   On the same day, the patient recovered from the events of 'loss of consciousness' and 'blood pressure decreased'.   On the next morning, 12-Nov-2021, the patient was feeling fine, her temperature was 98.6, and blood pressure was near normal 128/87, but the heart rate was still elevated at 100bpm.   The next morning, 13-Nov-2021, the patient woke up with slight fever, tightness in the chest and headache. The patient called her husband and by the time he came back home, her temperature had raised back to 99.8, and her blood pressure increased to 187/102 with 100bpm heart rate. The patient went to hospital for emergency treatment and by the time she got to the hospital her blood pressure was 217/110 and heart rate was 108. The patient was put on lisinopril and monitored throughout the day. The patient's blood pressure returned to normal around 5 p.m. and she was released home.   On 15-Nov-2021, in the evening, the patient still had temperature of 99.9.  On 16-Nov-2021, this morning, as reported, the patient woke up with normal temperature, however, two hours later she started to feel bad again. Her temperature returned to 99.8, blood pressure was 135/87, and the patient's husband gave her 10mg of lisinopril, and her blood pressure was under control.   On the same day, the patient recovered from the event of 'blood pressure increased'.   At the time of initial reporting, the patient had not recovered from the event of fever.   The outcome of all other events was unknown.  The reporter assessed the events as related to Fluad Quadrivalent. As reported, the patient's husband visited pharmacy where the patient was vaccinated, and pharmacist stated that there were no other reports of these symptoms. The patient's husband had concerns that this lot might had problem and if administered to someone not aware of these potential side effects, it could lead to much worse outcome.  The event loss of consciousness of was considered to be medically significant by a Physician within Seqirus's Pharmacovigilance and Risk Management Department.  Case updated on 26-Apr-2022: Correction made to information received on 16-Nov-2021: Regulatory authority was deleted from Intermediary field and Report Sent to Regulatory Authority by Reporter was changed from 'Yes' to 'Unk'. No changes in the narrative.  Company comment: A patient was vaccinated with the suspect product Fluad Quadrivalent. Within two days the patient developed influenza like illness with associated symptoms. After two days the patient experienced increased heart rate and lost consciousness with a drop in blood pressure. Five days after vaccination the patient experienced increased blood pressure. Information regarding the underlying medical history, related diagnostic findings and concomitant medications has not been provided. Based on chronological implausibility, causality for the event increased blood pressure is assessed as not related. Based on provided information and plausible time relationship, causality is assessed as possibly related.; Reporter's Comments: As reported, the patient's husband visited pharmacy where the patient was vaccinated, and pharmacist stated that there were no other reports of these symptoms. The patient's husband had concerns that this lot might had problem and if administered to someone not aware of these potential side effects, it could lead to much worse outcome.; Sender's Comments: A patient was vaccinated with the suspect product Fluad Quadrivalent. Within two days the patient developed influenza like illness with associated symptoms. After two days the patient experienced increased heart rate and lost consciousness with a drop in blood pressure. Five days after vaccination the patient experienced increased blood pressure. Information regarding the underlying medical history, related diagnostic findings and concomitant medications has not been provided. Based on chronological implausibility, causality for the event increased blood pressure is assessed as not related. Based on provided information and plausible time relationship, causality is assessed as possibly related.