In total she's had five blood clots/she had another clot in the left leg; she is getting dizzy; This is a spontaneous report received from contactable reporter(s) (Nurse) from medical information team. The reporter is the patient.  A 77-year-old female patient received BNT162b2 (BNT162B2), as dose 4 (booster), single (Batch/Lot number: unknown) at the age of 76 years, in right arm for covid-19 immunisation. The patient's relevant medical history included: "Left mastectomy done 23 years ago and she had chemo." (unspecified if ongoing), notes: Left mastectomy done 23 years ago, she had chemo; "Broken hip", start date: 2018 (unspecified if ongoing), notes: Broken hip; "Heart attack", start date: 2018 (unspecified if ongoing), notes: Had stents in her heart placed. He put her on plavix, aspirin 81mg, 2 heart pills; "diabetes" (unspecified if ongoing); "Pain" (unspecified if ongoing); "Blood thinner" (unspecified if ongoing). Concomitant medication(s) included: PLAVIX taken for thrombosis, start date: 2018 (ongoing); ASPIRIN 81 taken for thrombosis, start date: 2018 (ongoing). Past drug history included: Chemo, notes: Left mastectomy done 23 years ago, she had chemo at time after her mastectomy. Vaccination history included: BNT162b2 (Dose 1, SINGLE, Batch/lot number: EL9265, right arm.), administration date: 01Feb2021, when the patient was 76-year-old, for COVID-19 immunization; BNT162b2 (Dose 2, SINGLE, Lot: EN6203, Site: right arm), administration date: 23Feb2021, when the patient was 76-year-old, for COVID-19 immunization, reaction(s): "In total she's had five blood clots", "had some pain in her toe"; BNT162b2 (DOSE 3 (BOOSTER), SINGLE, Lot: EW0170, Site: Right arm), administration date: 20Oct2021, when the patient was 76-year-old, for COVID-19 immunization. The following information was reported: THROMBOSIS (medically significant), outcome "unknown", described as "In total she's had five blood clots/she had another clot in the left leg"; DIZZINESS (non-serious), outcome "unknown", described as "she is getting dizzy". The event "in total she's had five blood clots/she had another clot in the left leg" required physician office visit. The patient underwent the following laboratory tests and procedures: Ultrasound Doppler: Blood clot, notes: (Doctor name withheld)did a Doppler and said that she had another clot in the left leg. Therapeutic measures were taken as a result of thrombosis.  Clinical course: The caller on the other line is calling to share her experience from the Pfizer COVID-19 vaccine and booster shot. After getting the vaccine caller developed a blood clot in her leg. Caller is a retired LPN nurse that was calling about the Pfizer Covid-19 vaccines. She reported that she had one shot 01Feb2021. Then she had another injection 23Feb2021. She then had a booster on 20Oct2021. During that time, she went to the doctor at the wound center and said that her toe was sore. The doctor had done the caller's toenails in the 2 weeks before her to was sore. They did a doppler and the nurse told her that she had 5 blood clots in her legs. They called the cardiologist and the cardiologist said that they can put some stents in her legs, and they put 3 stents in in the right leg in Jul2021. They did some more stents in her left leg in Sep2021 at the heart center. Caller said that her previous cardiologist did the stents in Jul2021 and Sep2021. She took another booster dose and went to the doctor and said that her left leg has been giving her a problem. Doctor did a Doppler and said that she had another clot in the left leg. Her current cardiologist put in a venous closure device 12Jul2022. Caller said that Dr. (withheld) did a doppler and she had venous work on 07Jun2022. The nurse called her on 22Jun2022 and told her that she had a blood clot in the left leg. They scheduled her to get the venous closure device and she had that placed on 12Jul2022. Caller said that they put her to sleep and did a catheter and she stayed in the doctor's office for about 4 hours. She was getting dizzy. She is a senior and needs reminders for things. The doctor told her not to have another booster dose until a week after her procedure does not know why she is having these problems. She had this problem for a whole year. She looked it up on Google under the vaccine and cannot find anything on blood clots. She wanted to take another dose because she does not want to get Covid-19. Caller said that she is walking slow. She goes to 8 different doctors. She was thinking if she takes the vaccine again, she does not want to get another clot. She is nervous about taking it and wants to know if the blood clots are reported side effects. Weight: She said that she is trying to get her weight down to 170. She has not been able to fly because of the blood clots. Every time she gets rid of one blood clot, she gets another one. She had a mastectomy in the right arm 23 years ago and had chemo at that time after her mastectomy. Caller clarified that her mastectomy was in her left arm. Caller said that she was hospitalized a few times. Caller was not hospitalized for her blood clots and clarified that she only had outpatient procedures for her blood clots. She was hospitalized for a heart attack in 2018. She broke her hip first on 12Aug2018. She was in the hospital on the 12Aug2018 and was sent to a nursing home on the 15Aug2018. This was all before she had her Covid vaccines. She asked doctor to have another medication and he told her that she needed to stay with Plavix 75mg. She said that it is an old pill, and she would like something new. The doctor said that the new blood thinners have a lot of side effects.  The information on the batch/lot number for BNT162b2 has been requested and will be submitted if and when received.; Sender's Comments: Linked Report(s) : US-PFIZER INC-202200991069 same patient, different drug dose, similar event;