got sick after getting the vaccine; It was almost like flu like symptoms.; she felt yucky again; shiver; scatterbrained; rotten from the inside; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP) from medical information team for a Pfizer sponsored program (159558). The reporter is the patient.  A 77-year-old female patient received bnt162b2 (BNT162B2), administered in arm right, administration date 26Feb2021 (Lot number: EN6205) at the age of 77 years as dose 1, single for covid-19 immunization.   Relevant medical history included: "blood pressure" (unspecified if ongoing); "thyroid" (unspecified if ongoing). Concomitant medication(s) included: LEVOTHYROXINE taken for thyroiditis (ongoing); LOSARTAN taken for blood pressure measurement (ongoing).  The following information was reported: CHILLS (non-serious) with onset 2021, outcome "unknown", described as "shiver"; DISTURBANCE IN ATTENTION (non-serious) with onset 2021, outcome "unknown", described as "scatterbrained"; FEELING ABNORMAL (non-serious) with onset 2021, outcome "unknown", described as "rotten from the inside"; ILLNESS (non-serious) with onset 27Feb2021, outcome "unknown", described as "got sick after getting the vaccine"; INFLUENZA LIKE ILLNESS (non-serious) with onset 2021, outcome "unknown", described as "It was almost like flu like symptoms."; NAUSEA (non-serious) with onset 2021, outcome "unknown", described as "she felt yucky again".  Additional information: The patient received the first dose of the Pfizer covid vaccine on the 26Feb2021 and did not feel good for a week, then she took her usual medication levothyroxine, by afternoon she was feeling "shiver, scatterbrained, rotten from the inside". Her next dose was due next week. She wanted to know if there are any interaction of Pfizer covid vaccine with her thyroid medication levothyroxine (she stated the manufacture of her levothyroxine has discontinued it and the new levothyroxine from different manufacture don't look the same.). She did not feel well after the vaccine. This started the next day. It was almost like flu like symptoms. Her physician said to call. That is why she called. She didn't feel well. She felt sickish. She did not think much about it. About a week and a half ago tomorrow, she started feeling it. She takes a thyroid medication. The doctor also changed her blood pressure medication to a different prescription. She thought originally it was the Blood pressure medication making her feel this way. Then, a couple of days into it, that Saturday, she felt really hard to describe. She felt like she was shivering internally, nothing could be seen from the outside. Her insides felt rotten. She changed around her blood pressure medication, and took less instead of the increased amount the doctor wanted her too. A couple of days in to that, she took her thyroid medication 30 minutes before she eats like she is supposed to. Within 5 minutes of the thyroid medication, she felt yucky again. She does not know if it has to do with the COVID shot. The doctor changed her thyroid medications a couple of months ago. She had no trouble at first, but then bang all of the sudden realized it wasn't the blood pressure medication it was the thyroid medication making her feel awful.She got to wondering if the injection can cause any difficulties with medications? She just talked to Walmart. They stopped carrying the manufacturer that was producing her Levothyroxine. She had taken that manufacturer for years. In Dec2020, they put her on a different pill with a different manufacturer but still Levothyroxine. She has been trying to find the old medication. She was told that even though it is the same name, Levothyroxine and same dosage 112mcg, that one can work the other doesn't have to. The New manufacturer could be the whole problem. The Losartan was just increased from 50mg to 100mg. She thought maybe this was the problem at first. She gets her prescriptions every 90 days.  Description of Product Complaint: Description of complaint: The doctor changed her thyroid medications a couple of months ago. She had no trouble at first, but then bang all of the sudden realized it wasn't the blood pressure medication it was the thyroid medication making her feel awful.  No follow-up attempts are possible. No further information is expected.