issues with her thyroid; issues with her thyroid; Hair loss; heart palpitations; This is a spontaneous report received from contactable reporter(s) (Consumer or other non HCP) from product quality group. The reporter is the patient.  A 55 year-old female patient received bnt162b2 (BNT162B2), administered in arm right, administration date Aug2021 (Lot number: EW0187) as dose 3 (booster), single for covid-19 immunisation. Relevant medical history included: "breast cancer survivor" (unspecified if ongoing), notes: Its been 6 years; "thyroid" (ongoing). Concomitant medication(s) included: THYROXINE. Vaccination history included: Covid-19 vaccine (Primary immunization series complete, MANUFACTURER UNKNOWN), for Covid-19 Immunization.  The following information was reported: THYROID FUNCTION TEST ABNORMAL (non-serious), CONDITION AGGRAVATED (non-serious) all with onset Sep2021, outcome "unknown" and all described as "issues with her thyroid"; ALOPECIA (non-serious) with onset Sep2021, outcome "recovering", described as "Hair loss"; PALPITATIONS (non-serious) with onset Sep2021, outcome "recovering", described as "heart palpitations". The events "issues with her thyroid", "issues with her thyroid", "hair loss" and "heart palpitations" were evaluated at the physician office visit. Relevant laboratory tests and procedures are available in the appropriate section. Therapeutic measures were taken as a result of thyroid function test abnormal, condition aggravated, alopecia.  Additional information: After the booster dose the patient had issues with her thyroid and hair loss. The patient was originally calling about Paxlovid and was asking if these are side effects. She mentioned that if Paxlovid had the same side effects she would stop taking it. The patient is scared to take the Paxlovid if it will have the same side effects as the booster dose did. The booster messed up the patients thyroid. Weight provided as 122-125. The patient took the booster dose in the middle of Aug2021 and by the middle of Sep2021 her thyroid doctor had to adjust the dosage of her thyroid medicine and got it back right. The patient was taking Thyroxine- lot, NDC, and expiration date unknown. She was on thyroid medication for a long time and then 3-4 days after the booster dose it started. After they adjusted the dosage her hair loss improved a little but but not how it was. The booster dose also gave her heart palpitations and she had to see a heart doctor. She clarifies that her booster dose was the third dose of the covid vaccine. The patient does not have her thyroid blood work with her but her thyroid doctor has it.  The complaint for lack of effect of the PFIZERBIONTECH COVID-19 VACCINE INJECTABLE lot EW0187 was investigated. The investigation included reviewing manufacturing and packaging batch records, deviation investigations, analytical release test results, and an analysis of the complaint history for the reported lot. The final scope was determined to be the reported finished goods lot EW0187, fill lot EP8737, and the bulk formulated drug product lot EP8618. A complaint sample was not returned. No related quality issues were identified during the investigation. There is no impact on product quality. No root cause or CAPA were identified as the complaint was not confirmed. All release testing performed prior to the release of the reported batch was within specifications.  Follow-up attempts are completed. No further information is expected.