Thought he was having a stroke; Muscles shrinking; He had a lot of fatigue; When he would bend over he would get dizzy; Migraine headaches; Blood pressure goes up; Weight has been fluctuating; His neck got stiff; He lost muscle strength and muscle mass; He lost muscle strength and muscle mass; diagnosis of subclavial steal syndrome; Blood clots in both sides of his neck causing his veins to collapse; Veins collapsing; This is a spontaneous report received from contactable reporter(s) (Consumer or other non HCP) from medical information team. The reporter is the patient.  A 74-year-old male patient received BNT162b2, BNT162b2 omi ba.4-5 (BNT162B2, BNT162B2 OMI BA.4-5), as dose number unknown (booster), single (Batch/Lot number: unknown) for covid-19 immunisation; BNT162b2 (BNT162B2), as dose number unknown, single (Batch/Lot number: unknown) for covid-19 immunisation. The patient had no relevant medical history. The patient took concomitant medications. The following information was reported: THROMBOSIS (medically significant) with onset Dec2022, outcome "not recovered", described as "Blood clots in both sides of his neck causing his veins to collapse"; VEIN COLLAPSE (non-serious) with onset Dec2022, outcome "recovering", described as "Veins collapsing"; SUBCLAVIAN STEAL SYNDROME (non-serious) with onset Dec2022, outcome "not recovered", described as "diagnosis of subclavial steal syndrome"; CEREBROVASCULAR ACCIDENT (medically significant), outcome "unknown", described as "Thought he was having a stroke"; RHABDOMYOLYSIS (medically significant), outcome "not recovered", described as "Muscles shrinking"; FATIGUE (non-serious), outcome "unknown", described as "He had a lot of fatigue"; DIZZINESS (non-serious), outcome "not recovered", described as "When he would bend over he would get dizzy"; MIGRAINE (non-serious), outcome "not recovered", described as "Migraine headaches"; BLOOD PRESSURE INCREASED (non-serious), outcome "not recovered", described as "Blood pressure goes up"; WEIGHT FLUCTUATION (non-serious), outcome "not recovered", described as "Weight has been fluctuating"; MUSCULOSKELETAL STIFFNESS (non-serious), outcome "unknown", described as "His neck got stiff"; MUSCLE ATROPHY (non-serious), MUSCULAR WEAKNESS (non-serious), outcome "not recovered" and all described as "He lost muscle strength and muscle mass". The event "blood clots in both sides of his neck causing his veins to collapse" required physician office visit. The events "thought he was having a stroke", "when he would bend over he would get dizzy", "migraine headaches" and "his neck got stiff" required emergency room visit. The patient underwent the following laboratory tests and procedures: Blood pressure measurement: 150, notes: His blood pressure can go up to 150, 155, 160; 155, notes: His blood pressure can go up to 150, 155, 160; 160, notes: His blood pressure can go up to 150, 155, 160; Weight: 129, notes: when he used to weigh 129 and went down 128, 127, 124; 128, notes: when he used to weigh 129 and went down 128, 127, 124; 127, notes: when he used to weigh 129 and went down 128, 127, 124; 124, notes: when he used to weigh 129 and went down 128, 127, 124; 123, notes: Weight went down to 123 pounds. Therapeutic measures were taken as a result of thrombosis, subclavian steal syndrome, blood pressure increased.  Clinical course details: Patient stated he received the Pfizer primary COVID vaccine series and one booster dose, approximately 2.5 years ago. He never took the "second COVID booster shot" and was unsure if this second booster was recommended to be the monovalent or the bivalent vaccine. He currently is experiencing blood clots in both sides of his neck causing his veins to collapse, which was diagnosed as "subclavial steal". His doctors do not know how to treat it or what caused this to happen and state that this developed over time. Prior to diagnosis, he stated he noticed he had a lot of fatigue and when he would bend over he would get dizzy, but didn't know what was wrong. He currently takes a baby aspirin (manufacturer unknown) and doctor's will not perform surgery on him as it's too risky. He is scheduled for another MRI. He was also reading about sudden death occurring in patients who have had the COVID vaccine. (No further details provided on patients or manuf. of COVID vaccine he was speaking about). Additional information received on 07Mar2023: He hasn't told the doctors that it could be the COVID shot because he keeps forgetting. He forgets because of all the things he has to go through. Has another MRI where he will be injected with iodine on 15th of this month. His HCP took out 9 vials of blood on him. His vascular doctor doesn't know what is causing it. He can't have surgery because it is risky and not guaranteed. He went in twice to ER for same reason. Clarified the reason he went to the ER was his neck got stiff, bad headaches, dizzy, and thought he was having a stroke. ER thought it was the tendons in his neck and he was given muscle relaxers. Only thing he is doing right now is not ruling anything out. Could be food, air, anything, doesn't know what is causing it. This isn't hereditary, his mother passed away not from clotting nor his dad. He was seeing three HCPs and never explained to them that it could be the shot. Maybe yes, maybe no. Not ruling anything out. When his vascular HCP said he didn't know what was causing it and he doesn't either. HCP didn't know what to do for him. He was also seeing a specialist clarified to a rheumatologist for his back of neck for veins back there. Was referred to the rheumatologist by his vascular doctor. The rheumatologist is the one that is handling it, the one who ordered 9 vials of blood pulled, and for an MRI with injection of iodine into him. Was recommended to this doctor from his vascular doctor he was seeing. Rheumatologist will do an MRI on top of neck all the way down to his stomach. Declined to provide rheumatologist information and provided his general HCP information. His subclavial steel syndrome was diagnosed in Dec2022 but had had it for a while. Clarified it isn't new but it has been there but he doesn't know how long. Not getting any treatment besides baby aspirin and testing. HCP was trying to figure out how to treat him. The outcome was reported as worse, now he gets migraine headaches and his weight was also fluctuating. Weight went down to 123 pounds when he used to weigh 129 and went down 128, 127, 124. When he eats doesn't feel like eating, doesn't have an appetite. The clots in veins on sides of neck started in Dec2022 but his HCP is still not diagnosing the problem and doesn't know how to treat it or what is related. Feels fatigue a lot or very tired which started about a year and a half ago. Give and take situation, sometimes good, sometimes bad. Sometimes he wakes up like he has a hangover. He gets migraine headaches (in the past 6, months 8 months, 9 months, give and take almost a year) and sometimes gets dizzy (happens every now and again. when he bends down, turns head too quick he gets dizzy. Started about a year ago. Has not improved at all.). Doesn't want to do anything. Maybe it is caused by the chili he eats since he is (withheld). His veins are shutting down and collapsing. He feel a little better, not kidding it is not a hoax. He has been drinking a lot of beet juice and noticed he felt different and also garlic. He feels different and his blood pressure has gone down. Not a hoax and not in his head. He is taking blood pressure pills right now, 100mg generic brand, and knows the blood pressure pills are rotten and no good for him and doesn't help him. Blood pressure goes up was diagnosed maybe 2 years ago. He suffered with high blood pressure for quite a while but not this high. Had it borderline but not the way it is going right now. Could take his blood pressure right now and guarantees it is high, but he doesn't know why. Could see if he was overweight but he isn't. Outcome: Has worsened but sometimes it is ok. Weight has been fluctuating which started about a year ago. He lost muscle strength and muscle mass. Used to have muscle and doesn't any more, was shrinking and that is bad. Weight goes up and down. Sometimes he can eat a lot and still lose weight. Doesn't know how he is losing weight because he is eating. Muscles shrinking: Start Date: About a year now or less, give or take, 12 months, 9 months. Used to have muscle a lot of muscle. Clarified it was not fat it was muscle. Wants to go to the gym to try and start getting muscles and strength back but doesn't know if clotting can make it worse by stress. His artery may shut down. He has to do something, otherwise he will rot.  The information on the batch/lot number for BNT162b2, BNT162b2 omi ba.4-5, BNT162b2 has been requested and will be submitted if and when received.