postural instability due to probable cerebral ischemia; probable cerebral ischemia; this is a spontaneous report received from a contactable reporter(s) (physician) from the regulatory authority-web. regulatory number: it-minisal02-842621. a 85 year-old male patient received bnt162b2 (comirnaty), intramuscular, administered in arm left, administration date 12oct2021 15:00 (lot number: fg6270, expiration date: 31mar2022) as dose 3 (booster), 0.3 ml single for covid-19 immunisation. the patient's relevant medical history and concomitant medications were not reported. vaccination history included: covid-19 vaccine (first dose, unknown manufacturer), for covid-19 immunisation; covid-19 vaccine (second dose, unknown manufacturer), for covid-19 immunisation. the following information was reported: balance disorder (hospitalization) with onset 05feb2022, outcome "unknown", described as "postural instability due to probable cerebral ischemia"; cerebral ischaemia (hospitalization) with onset 05feb2022, outcome "unknown", described as "probable cerebral ischemia". no follow-up attempts are possible. no further information is expected