I can not hear out of my right ear; This is a spontaneous report from a contactable other healthcare professional (patient reported for herself). A 71-year-old female patient received bnt162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE, Formulation: Solution for injection, Batch/Lot Number: FC3183), via an unspecified route of administration, administered in right arm on 25Aug2021 (at the age of 71-year-old) as dose number unknown, single for COVID-19 immunisation. Medical history included hypertension from an unknown date and unknown if ongoing Verbatim: Hypertension, autoimmune disorder from an unknown date and unknown if ongoing Verbatim: Auto Immune disease, rheumatoid arthritis from an unknown date and unknown if ongoing Verbatim: Progression of rheumatoid arthritis, degenerative bone disease from an unknown date and unknown if ongoing Verbatim: Degenerative bone disease, neoplasm malignant from an unknown date and unknown if ongoing Verbatim: Cancer I am a cancer survivor, twice, chemotherapy from an unknown date and unknown if ongoing 13 years ago, radiotherapy from an unknown date and unknown if ongoing 13 years ago. Retired nurse stated, "I am a cancer survivor, twice and I went through the whole thing, I went to the chemo, I went to the Radiation and that was 13 years ago. So, it's a long time ago." No relevant family history was reported. Concomitant medications included bisacodyl (LAXATIN) taken for an unspecified indication, start and stop date were not reported. The patient did not receive any other vaccines within 4 weeks prior to the COVID vaccine. On 26Aug2021, the patient experienced I cannot hear out of my right ear. RN confirmed the name of the product as Pfizer Covid-19 Vaccine. RN stated, "I used to be a nurse, but I am retired now." (Hence, captured as Retired Nurse). RN stated," It might have started yesterday but she really was not aware, but it was this morning when she was taking and noticed change in the ear and could not hear." "Yes, this morning I started taking new medication which was Morphine 15mg of this." RN stated," Morphine that is the new one. Okay you want to know rest of my Medication. First one was the Morphine, I take Laxatin which is Prozac and I take 20mg once a day." Therapeutic measures were taken as a result of I cannot hear out of my right ear (deafness). Retired nurse (RN) stated, "I had the Pfizer injection yesterday afternoon and now, Wednesday I had the vaccination, and I cannot hear out of my right ear, I don't know it's formed the (Incomplete sentence), I don't know." The patient underwent lab tests and procedures which included blood test: unknown on an unspecified date in Jul2021. The outcome of the event was reported not resolved.; Sender's Comments: Based on the temporal relation, the association between the event of deafness unilateral and the suspect product of BNT162B2 cannot be completely ruled out.  The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to regulatory authorities, Ethics Committees, and Investigators, as appropriate.