Hypothyroid returned; She will be discussing something, suddenly goes blank, then never regains it until maybe a minute or so later; States she doesn't think of dementia, she has just never had this before and it is terrible; she felt bad after her second shot; she was sluggish; picking up weight/ gained a little weight; pain (in both leg) still goes from around the knee/calf, inner upper side of leg, almost up to where the leg connects; pain (in both leg) still goes from around the knee/calf, inner upper side of leg, almost up to where the leg connects; cognitive deficiency/ cognitive Issues; forgetfulness/ can't remember yesterday; muscle weakness and pain in both legs; muscle weakness and pain in both legs; This is a spontaneous report received from contactable reporter (consumer or other non-HCP) from Medical Information Team. The reporter is the patient.  A 74-year-old female patient received bnt162b2 (BNT162B2) via an unspecified route of administration on 11May2021 (batch/lot number: EW0168) at the age of 73 years old, as DOSE 2, SINGLE for COVID-19 immunization. Relevant medical history included: "Osteopenia" (ongoing), notes: this condition has been ongoing for 2-3 years; "Hypothyroidism" (ongoing), notes: Found in dexa scans and blood work., Patient had this condition as a young kid and that it resolved in her 20's after she had her child; "Her weight fluctuates between 175-180 pounds" (unspecified if ongoing). Concomitant medication included: LEVOTHYROXINE taken for hypothyroidism (ongoing). Vaccination history included: Bnt162b2 (first dose, via an unspecified route of administration (batch/lot number: EW0169) as DOSE 1, SINGLE), administration date: 20Apr2021, when the patient was 73 years old, for COVID-19 immunization.  The following information was reported: HYPOTHYROIDISM (medically significant), outcome "unknown" described as "Hypothyroid returned"; MENTAL IMPAIRMENT (medically significant), outcome "not recovered" described as "She will be discussing something, suddenly goes blank, then never regains it until maybe a minute or so later"; DEMENTIA (medically significant), outcome "not recovered" described as "States she doesn't think of dementia, she has just never had this before and it is terrible"; MUSCULAR WEAKNESS (non-serious), MYALGIA (non-serious) all with onset Aug2021, outcome "not recovered" and all described as "muscle weakness and pain in both legs"; COGNITIVE DISORDER (non-serious) with onset Nov2021, outcome "not recovered" described as "cognitive deficiency/ cognitive Issues"; MEMORY IMPAIRMENT (non-serious) with onset Nov2021, outcome "not recovered" described as "forgetfulness/ can't remember yesterday"; FEELING ABNORMAL (non-serious), outcome "not recovered" described as "she felt bad after her second shot"; SLUGGISHNESS (non-serious), outcome "not recovered" described as "she was sluggish"; WEIGHT INCREASED (non-serious), outcome "not recovered" described as "picking up weight/ gained a little weight"; PAIN IN EXTREMITY (non-serious), ARTHRALGIA (non-serious), outcome "not recovered" and all described as "pain (in both leg) still goes from around the knee/calf, inner upper side of leg, almost up to where the leg connects." The events were evaluated at the physician office visit. The patient underwent the following laboratory tests and procedures: blood test: unknown results; Dexa scans (bone densitometry): unknown results; Tests for osteopenia: hypothyroid returned, notes: Hypothyroid returned; It was rediscovered during her osteopenia testing over the last year or two; weight: unknown, notes: picking up weight/ gained a little weight. Therapeutic measures were taken as a result of hypothyroidism.  The clinical course was reported as follows: Patient received her 2nd dose on 11May2021, stated since around August of last year (2021), she has muscle weakness and pain in both legs. The muscle pain is still continuous, like whenever she's putting on some weight, it's really painful. She also noticed some cognitive deficiency or forgetfulness since November of last year (2021). She received Reclast infusion back in November of last year (2021) and she was told that it wasn't contraindicated after getting the vaccine. She wanted to know if that is accurate and wanted to know if there are cases like this that has been reported. She's declining to get the booster shot because of what's she's experiencing right now. The patient further stated that she is seeing doctors in the next month or so to see if they can work it out.  She is refusing to get the booster dose of the vaccine due to her not great effects from the first two vaccines. She got the second shot last spring.  At the end of fall she started having muscle weakness and pain in both legs. It is particularly on her right side and will go away for a moment; but then if she is doing any weight-bearing like climbing stairs, the weakness returns. Patient stated what is really concerning is her cognitive ability.  She is a writer and has been active all of her life as a mother, wife, volunteer, and a professional.  She would experience the normal momentary whoops.  Her husband is an attorney and asked her did she realize what was going on.  She will be discussing something, suddenly goes blank, then never regains it until maybe a minute or so later.  States that it is driving her and her husband nuts.  Caller says that it is not something she has ever had before she can only track that it began after the shots. She desperately wants Pfizer to collect this data.  States that she lives in (state) and that her doctors are in (state), she is sure they will attack her problem. Patient says that she has a question: Could the Pfizer Vaccine have been contraindicated with another drug?  States she finished her vaccines, she thinks in June; then in November she had a Reclast infusion for osteopenia.  Stated that her issues got worse after that.  She asked them about it at the time. Patient also stated that she is not a little old lady though.  She moves, moves, moves, and runs a health program. Her weight fluctuates between 175-180 pounds. She is currently travelling but should be home in a week or so. Her doctor works out of (institute name).  She only declines for him to be contacted because she is going to see him on 25Mar2022 and then, she will give him the entire picture of what has been going on with her. Muscle weakness, pain in both legs: patient states that she didn't notice these symptoms until about Aug2021 or Sep2021. Cognitive Issues:  this was ongoing after the second shot; more so in Nov2021, going into Dec2021. She felt bad after her second shot, she went to bed, and then that was over. Patient also mentioned Expiry Date of vaccines:  Unknown; the letters on the card are tiny and she is looking for her magnifying glass.  She bought it to read little things, now she cannot find it. She got her first infusion of Reclast for Osteopenia in Nov2021.  She cannot remember the exact date, thinks it was around the fifth.  NDC, Lot Number, Expiry Date for this medication are unknown. She has been having tests for osteopenia for the past year or two.  She has been having dexa scans and blood work.  States that's when they found she has hypothyroid.  She had it as a kid and remembers taking a little white pill.  Caller says that in her 20's after her first child she no longer had hypothyroid.  States that it was found to have returned during her tests for osteopenia. She was sluggish and picking up weight.  Since it was rediscovered she has been taking Levothyroxine. Patient denies any other medications, medical conditions, labs, testing, or treatments relevant to these events. She asked the question about contraindications with the Reclast when she got the infusion and was told there were no problems. This winter she was away and there was an indoor pool.  She went swimming four times a week, she walks 4-5 miles a day, none of this is not ordinary for her to do.  She was trying to pay attention with her legs during that time, but it did not improve.  She thought maybe it was because she had been lazy, and maybe gained a little weight.  States the pain (in both leg) still goes from around the knee/calf, inner upper side of leg, almost up to where the leg connects.  She had it on the left side, that seems to have gone away; although it went more to the right side. She thought this information was important to share for Pfizer's data gathering.  She can't remember yesterday and that bothers her.  States that something is wrong, she doesn't know what.  She doesn't think of dementia, she has just never had this before and it is terrible.  It has all just come on since the shots.  Follow-up attempts are completed. No further information is expected.