uncommonly high blood pressure that she never had before/blood pressure was 276/199; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP). The reporter is the patient.  A 55 year-old female patient received bnt162b2 (BNT162B2), administered in arm left, administration date 06Jan2022 13:00 (Lot number: 330258D) at the age of 55 years as dose 3 (booster), single for covid-19 immunisation. Relevant medical history included: "MS" (ongoing), notes: Diagnosed prior to Pfizer Covid vaccine; caller states she has had MS for 8 years.; "low blood pressure" (unspecified if ongoing), notes: always had low blood pressure. There were no concomitant medications. Vaccination history included: Bnt162b2 (1st dose of the Pfizer Covid vaccine, lot EP7534), administration date: 18Mar2021, when the patient was 54 years old, for COVID-19 Immunization; Bnt162b2 (2nd dose of the Pfizer Covid vaccine  , lot EW0153), administration date: 08Apr2021, when the patient was 55 years old, for COVID-19 Immunization. The following information was reported: HYPERTENSION (hospitalization, medically significant) with onset Jan2022, outcome "not recovered", described as "uncommonly high blood pressure that she never had before/blood pressure was 276/199". The patient was hospitalized for hypertension (start date: 09Feb2022, discharge date: 11Feb2022, hospitalization duration: 2 day(s)). The event "uncommonly high blood pressure that she never had before/blood pressure was 276/199" was evaluated at the emergency room visit. The patient underwent the following laboratory tests and procedures: blood pressure measurement: (Jan2022) 276/199; echocardiogram: (Feb2022) cardiac workup came out fine; ultrasound scan: (Feb2022) cardiac workup came out fine. Therapeutic measures were taken as a result of hypertension with Valsartan 80mg tablets and Carvedilol 6.25mg.  Clinical course: The patient was calling about the Pfizer covid vaccine and stated that she wanted to report that she got both the Pfizer covid vaccines and the booster also and had MS. Caller stated that as soon as she got the booster vaccine, she was in the emergency room with uncommonly high blood pressure that she never had before and always had low blood pressure and it got to the point where she was at stroke level and when she got to the emergency room, her blood pressure was 276/199. Her blood pressure began to rise it seemed like towards the end of Jan2022 which was after her booster dose of the Pfizer Covid vaccine and it was the first time she had that and always had low blood pressure and has a blood pressure machine at home; stated she knew she was experiencing a horrible worse than a migraine and took her blood pressure at home and it was in the 200s when she went to the emergency room and she got to the emergency room and they took her blood pressure and treated her like a stroke victim. The patient's high blood pressure was still ongoing and she was still having that problem and when she was in the hospital, the cardiologist did a complete workup of her heart and it came out ok and they could not give her any answers of why that was happening and she was still dealing with the issue.  She was prescribed two different blood pressure medications and they were the only two that worked for her and she then took her blood pressure three times per day and even with that was having to call the on call doctor and the blood pressure was going really high and they were having her double up on the medications to get it down; states she had no lot numbers or names of the medications that did not work for her but the two she was taking were Valsartan 80mg tablets and was supposed to take it once per day and it was an orange pharmacy bottle and did not have the lot, expiry date or NDC as it was a pharmacy bottle; states the second medication was Carvedilol 6.25mg and she was supposed to take it once every 12 hours and it was also an orange pharmacy bottle and does not have the lot, expiry date or NDC as it was a pharmacy bottle. The vaccination was given in the afternoon around 1:00pm. Anatomical location of administration of Pfizer vaccine considered as suspect was provided as upper left arm. The vaccination administered at pharmacy and it was not a Military facility. No additional vaccines administered on same date of the Pfizer suspect and was not treated with any medication prior vaccinations (within 4 weeks). MS diagnosed 8 years ago and family medical history relevant to AE(s) was provided as none. The patient had MS and was not allowed to get vaccines but got this because of covid regarding the Pfizer Covid vaccines. Caller stated that for testing they basically did a complete cardiac workup on her while she was in the hospital and they did an echo and an ultrasound and wanted to make sure her heart was ok and basically the cardiologist said those came out fine. Caller stated that she noticed when they did clinical trials that nobody in the clinical trials had MS or lupus or anything and there was no way to follow up to see how they were doing; stated she was just concerned also about other people that have MS or lupus and how they were doing for those kinds of concerns.   Follow-up attempts are completed. No further information is expected.