experienced hearing loss in his left ear/hearing loss on both ears; his right ear seems like there is water in there or it is underwater/left ear sounds like everything is echoing; immediately things were muffled; This is a spontaneous report from a contactable consumer (patient). A 61-year-old male patient received BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE), via an unspecified route of administration, administered in right upper arm on 27Apr2021 11:00 (Batch/Lot Number: EWO171; Expiration Date: Aug2021) as 1st dose, single for covid-19 immunization. Medical history including hearing was about 80 percent in the left ear/loss of 20-30 percent which started 10 years ago when the patient was 51. The patient has no concomitant medications. No additional vaccines administered on same date of the Pfizer suspect and no prior vaccinations within 4 weeks. After receiving a dose of Pfizer Covid-19 vaccine on 27Apr2021, the patient experienced hearing loss in his left ear, it was barely noticeable but today (04May2021 12:00) there was a dramatic shift and he experienced hearing loss on both ears, it was instantaneous. The patient wanted to know if there are any reports of hearing loss and when could it go away. He has a hearing issue in his left ear that he has had, his hearing was about 80 percent in the left ear and in the right ear it was a 100 percent. Today, at noon he has almost lost his hearing in his left ear and his right ear seems like there is water in there or it is underwater. His left ear sounds like everything is echoing but, he can hear the call handler just fine. His right ear was perfect and now it is messed up. He is worried about that. The patient wonders why that happened and why did they both go. He reported that the shot may have had something to do with it and if it does, what should he do or maybe he is just getting old. He cannot hear in the left ear much; he was just testing it while on hold listening to the music to see how much he had. He felt like there is water in it, not a little, a lot of water and it echoes a little bit and seemed like it's underwater. Started 10 years ago when he was 51, he lost 20-30 percent and it stopped as far as he could tell. He did not get checked out then because he could hear clearly. Today at 12 pm, and it was not gradual, it was like turning a light on, immediately things were muffled. Even when he was putting his hands over his ears, there was like an echo. He was on the phone with his wife at the time. He did not know what happened, so, he went to work, and nothing is changed. He told her something just happened to his ears. He thought of doing something in the meantime and not trying to wait for it to get better. Right ear feels like it is underwater, maybe the left ear is affecting the right the or the weaker ear is being affected more. The right ear is the stronger ear over the left ear. That is what bothering him. His weaker ear is being affected more than his good ear, which his right ear has always been the stronger ear and he never had problems before with his right ear. It was a dramatic switch today at 12pm and his ears have been that way ever since. The left ear feels like its underwater, so much even if he blocks that ear with his finger or his palm. Still there is something going on in both ears. He did not notice the right ear because the other ear was such a shock and he was just dealing with that. He noticed the right side too after trying to see if he could hear out of the left. He had no baseline to go off of for sure or a history. No baseline to go from other than this hearing change of event, which may be totally him. He wanted to see if there is anything related to this because it was so dramatic. The events were not treated. The outcome of the event "experienced hearing loss in his left ear/hearing loss on both ears" was not recovered while the other events were unknown.  Information on Lot/Batch number was available. Additional information has been requested.