2nd dose and booster were worse with lows; My lows have been in the 30-40 randomly day and night/In fact my thyroid went severely low was only at .084; drops in her blood sugars occurred after the first, second, and third doses of the vaccines.; sore arm; every time she gets it she has severe lows; her blood sugars won't go up since she got the vaccine; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP) from medical information team. The reporter is the patient.  A 50-year-old female patient received BNT162b2 (BNT162B2), on 09Apr2021 as dose 2, single (Lot number: EW0162), in left arm and on 21Oct2021 as dose 3 ( booster),single (Lot number: FF2589) at the age of 49 , in left arm for covid-19 immunisation. The patient's relevant medical history included: "Type 1 diabetic" (unspecified if ongoing), notes: diagnosed around age 30.; "hypothyroidism" (unspecified if ongoing), notes: 12-14 years ago and they caught the severe low recently.; "painful bladder syndrome" (unspecified if ongoing), notes: diagnosed about 1.5 -2 years ago.; "fibromyalgia" (unspecified if ongoing), notes: she thinks diagnosed in 2015. Concomitant medication(s) included: LEVOTHYROXINE taken for hypothyroidism. Vaccination history included: coviD-19 vaccine (Dose 1, Lot no:ER2613, anatomical location: arm left), administration date: 18Mar2021, for COVID-19 immunization; Flu vaccine; Pneumonia vaccine; Tetanus vaccine. The following information was reported: DIABETES MELLITUS (medically significant), outcome "unknown", described as "2nd dose and booster were worse with lows"; HYPOTHYROIDISM (medically significant), outcome "unknown", described as "My lows have been in the 30-40 randomly day and night/In fact my thyroid went severely low was only at .084"; BLOOD GLUCOSE DECREASED (non-serious), outcome "unknown", described as "drops in her blood sugars occurred after the first, second, and third doses of the vaccines."; PAIN IN EXTREMITY (non-serious), outcome "unknown", described as "sore arm"; FATIGUE (non-serious), outcome "unknown", described as "every time she gets it she has severe lows"; HYPOGLYCAEMIA (non-serious), outcome "unknown", described as "her blood sugars won't go up since she got the vaccine". The patient underwent the following laboratory tests and procedures: Blood glucose decreased: (29Mar2022) Low; Blood glucose fluctuation: (unspecified date) kinda crazy up and down, notes: the 1st day was; Thyroid hormones decreased: (unspecified date) at .084.  Clinical Course: Patient reported having trouble concentrating during the conversation with agent. She wanted to know if others with Type 1 diabetes experienced low blood sugar after the vaccine. Agent encouraged her to contact HCP and to disconnect from call if condition worsened. She was very good at controlling her diabetes and that drops in her blood sugars occurred after the first, second, and third doses of the vaccines. She said that she was in communication with her diabetes specialist and that she always had some sugar with her whether it was food or drink. LAB-1457-22.0; Revised: 29Mar2022 for caller using- terms "diabetes", "glucose", "low", "blood sugar". I'm writing you because the Pfizer Covid vaccination and booster shot what I chosen and stuck with for all 4 shots. I had been trying to reach out through research and through my doctors because of the effects the vaccine was having on me. I'm a type 1 diabetic, when I got the2nd dose and booster were worse with lows this last booster even worse lows. Was anyone else having this? No report related to a study or programme. She was asking if anyone had said anything about Type 1 diabetes and the vaccination and severe low blood sugars after vaccinations. She was not complaining. She was in her car waiting for her blood sugar to come up and can't concentrate well. She did not need emergent help right now. She got all 4 Pfizer, Her blood sugars won't went up since she got the vaccine. Stated that every time she gets it she had severe lows. Other people might be blowing it off because they were diabetic. States it was only after the vaccination that it happened. Pfizer Covid vaccine 2 on 09Apr2021. Caller did not have NDC, expiry or dose to provide. lot EW0162. Her blood sugar the 1st day was kinda crazy up and down and the next day they started crashing on her overnight. She had a Dexcom now thank God and you get them that often you don't wake up. They started getting more severe and would spend a couple of hours drinking as much juice as she can and eating foods to stabilize her sugar and that works for half an hour to an hour. She relayed that she has already had 2 lows this morning and was up all night in the 50's and 60's and could not get them above 70 for a very long time. She felt like she was ok now. The Night before she spent 2 hours at 40 and then was able to sleep for an hour and then it crashed down again. It was just all night long and she got maybe an hour and a half of sleep and that was it. Then it crashed again this morning. It was 73 and had an arrow down meaning it was going down fast. History of all previous immunization with the Pfizer vaccine considered as suspect as Pfizer Covid vaccine 3, left arm in the morning between 7-9 AM. Pfizer Covid vaccine 2 got it in her left arm in the morning. No Additional vaccines administered on Same Date of the Pfizer Suspect. In Oct2021 she got the flu vaccine, tetanus vaccine, and another one she can't recall the name of all in a week and a half. Not on the same day. It was a pneumonia shot. she would have gotten the flu vaccine Prior Vaccinations within 4 weeks. States she got the pneumonia shot before Covid hit and waited until later for the second. Caller did not recall the name of the Tetanus shot but she for sure did it in her other arm, right arm.  No follow-up attempts are possible. No further information is expected.