TSH was 0.25/negative impact to her TSH reading/the results for the lab for TSH were really low; muscles across her shoulder and down her arms; there was pain; muscles across her shoulder and down her arms; there was pain, stiffness; had to decrease her Synthroid dose for 3 weeks after vaccination and had some lab results changed/thyroid reactions; feeling funny; dizzy/dizziness; short of breath; numbness in her face; This is a spontaneous report from a contactable consumer (patient). A 67-years-old female patient received bnt162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE), dose 2 via an unspecified route of administration on 28Feb2021 (Batch/Lot Number: EN6200; Expiration Date: Jun2021) (at age 67-years-old) as dose 2, single for covid-19 immunisation. The patient received the 1st dose on 10Feb2021(lot number: EN6201, expiry date: Jun2021) at age 67-years-old. Historical vaccine also included pneumonia vaccine and patient experienced muscular issues. Medical history included ongoing hypothyroidism from last 17 years. Concomitant medication(s) included levothyroxine sodium (SYNTHROID) taken for hypothyroidism, start and stop date were not reported. Patient had the adverse event at first, she got it in the muscles across her shoulder and down her arms; there was pain, stiffness, and numbness. She did the follow-up thing for a week after that. These were after the second dose, and then six weeks later, she had a negative impact to her thyroid. She was starting to see adverse reaction with her hypothyroidism, which she has been on thyroid medication for 17 years, she gets a blood test every year and tracks it, and it was fine all those years, she had been on the same dosage. 6 weeks after her second dose of the Pfizer COVID-19 vaccine she started feeling funny, dizzy, short of breath and they did labs and her TSH was 0.25, so her doctor thought maybe her dose needed to be changed back to original dose. Her second dose, she had muscle issues again and numbness in her face, which that portion went away. She treated it by putting ice on it about 4 hours. The thyroid issue troubles her because she was stable all these years and now all of a sudden she has been getting negative impact to her TSH reading. The muscular part was similar to reaction to COVID vaccine. Her doctor sent her to see an endocrinologist, and because Pfizer doesn't know impact on hypothyroidism, she thought they should know they have a patient with negative impact. She has been seeing more things online where people had that issue, which her concern is, if all of a sudden she needs to get a booster shot she doesn't know if she would want a booster after all this. She says her symptoms improved over time, and her doctor had her going back to her original dose of Synthroid. After the vaccine she has used a TENS machine for her muscles issues, which were improving. She had a similar reaction to other vaccines in the past, for example the pneumonia vaccine (NDC/LOT/EXP: Unknown) which gave her similar muscular issues. Her doctor about it and they didn't think there was any issue, and with the flu booster shot (NDC/LOT/EXP: Unknown) she also had a similar reaction. Patient had both of those vaccines before getting the Pfizer vaccine, and now she got a similar reaction to it, but worse, especially the muscular part of it. Then the thyroid started, and she had dizziness that was quite severe for a couple weeks and she had her do the Epley maneuvers which are head movements to readjust crystals in your head and prescribed her Meclizine, and did tests to make sure not her inner ear. The results for the lab for TSH were really low and tell what messed her up big time. She never took the Meclizine, she just did Epley maneuvers because she doesn't like taking pills or vaccines because her body has negative reactions to things. The original dose provided of Synthroid 0.075 to 0.75mcg. She was on that dose 17 years, then her doctor reduced her to 0.50mcg and symptoms only got worse on the lower dose which she took for three weeks. Her antibody test and thyroid peroxidase were elevated, her thyroid globulin antibody was almost 1200 which is really high, which was why her doctor got nervous and sent her to an endocrinologist. Patient wanted to run some of this by them, she doesn't know if she is a candidate for a booster if it is required after what happened. She says now she believes she is getting better, and wants to question Pfizer is this typical based on cases she reads online of people in similar or worse situations that had this and recovered over time, which also happened in her case: is she one of those individuals who had a thyroid reaction to the Pfizer COVID-19 vaccine and should she avoid getting a booster shot. Outcome of the event of feeling funny, dizzy and short of breath was unknown, while for the remaining events war recovering. Patient recovered from numbness in face.  Follow-up attempts are completed. No further information is expected.