weakness/getting like weak; hallucinations or dreams/hallucinating and dreaming; handshaking/hands were shaking; walking has gotten worse; had other thing would her kidney disease problem but since Monday after that it got worse; had other thing would her kidney disease problem but since Monday after that it got worse; his mother got Moderna for all her four other COVID-19 vaccine. Her mother took a Pfizer COVID-19 .; His mothers talking is not great; her tongue is sore; has a walker; This is a spontaneous report received from contactable reporter(s) (Consumer or other non HCP) from medical information team.  An 85-year-old female patient received bnt162b2 omi xbb.1.5 (COMIRNATY (2023-2024 FORMULA)), on 18Sep2023 as dose 1, single (Batch/Lot number: unknown) at the age of 85 years for covid-19 immunisation. The patient's relevant medical history included: "She had kidney disease" (unspecified if ongoing). The patient's concomitant medications were not reported. Vaccination history included: Moderna covid-19 vaccine (Dose 1, Single), administration date: 2021, for COVID-19 Immunization; Moderna covid-19 vaccine (Dose 2, Single), administration date: 2021, for COVID-19 Immunization; Moderna covid-19 vaccine (Dose 3 (Booster), Single), administration date: 2021, for COVID-19 Immunization; Moderna covid-19 vaccine (Dose 4 (Booster), Single), administration date: 2021, for COVID-19 Immunization. The following information was reported: SPEECH DISORDER (non-serious) with onset Sep2023, outcome "unknown", described as "His mothers talking is not great"; WALKING AID USER (non-serious) with onset Sep2023, outcome "unknown", described as "has a walker"; GLOSSODYNIA (non-serious) with onset Sep2023, outcome "unknown", described as "her tongue is sore"; CONDITION AGGRAVATED (non-serious), RENAL DISORDER (non-serious) all with onset 18Sep2023, outcome "unknown" and all described as "had other thing would her kidney disease problem but since Monday after that it got worse"; INTERCHANGE OF VACCINE PRODUCTS (medically significant) with onset 18Sep2023, outcome "unknown", described as "his mother got Moderna for all her four other COVID-19 vaccine. Her mother took a Pfizer COVID-19 ."; HALLUCINATION (medically significant) with onset 19Sep2023, outcome "unknown", described as "hallucinations or dreams/hallucinating and dreaming"; TREMOR (non-serious) with onset 19Sep2023, outcome "unknown", described as "handshaking/hands were shaking"; GAIT DISTURBANCE (non-serious) with onset 19Sep2023, outcome "unknown", described as "walking has gotten worse"; ASTHENIA (non-serious) with onset 20Sep2023, outcome "unknown", described as "weakness/getting like weak". The event "had other thing would her kidney disease problem but since monday after that it got worse" required physician office visit and emergency room visit. The patient underwent the following laboratory tests and procedures: Blood test: (19Sep2023) Unknown results, notes: They havent got the results yet.  Clinical course: Caller is the patients son. He said that his mother got Moderna for all her four other COVID-19 vaccine shots back in 2021. He called for guidance and was told it was fine to take the Pfizer brand. This is the first time that her mother took a Pfizer COVID-19 shot. The pharmacy receipt said it is the Pfizers COVID-19 SDV vaccine 23-24 formula. His mother is 85-year-old and has kidney disease. His mother got the Pfizer booster shot last Monday. His mother started experiencing the following: hallucinations or dreams, handshaking, and walking has gotten worse. He wants to know their relation to the vaccine. He mentioned that they were able to consult with the kidney doctor and got blood tests done on Tuesday, and his mother was fine. They have not got the results yet. When he called about the side effects his mother is now experiencing, he was told by the secretary to contact a primary health care doctor. Afterwards, they were referred to go to the emergency room. He said that the hallucinations comes and goes, sometimes she knows what she is talking about and sometimes she is out of it. Once in a while, every couple of hours, she gets these hallucinations, and walking to the bathroom is hard. Like her mobility is not there. His mothers talking is not great and her tongue is sore. He thought the weakness can be associated with the vaccine. She has had no nausea or headache. He states the dreams or hallucinations wake her up. She had the Pfizer Booster (later clarified as Pfizer COVID-19 Booster vaccine) on Monday and now, yesterday she started like, getting like weak and her hands were shaking and like, getting like, not hallucinating, like dreams and stuff and he woke her up like so he is just trying to say this part of the Pfizer, the side effects, you think? Because on Tuesday she went to her kidney doctor and she had blood test and some other stuff but her doctor did not call back relating of that, her blood test should be report yet. Reporter stated she never had this before. She had other thing would her kidney disease problem but since Monday after that it got worse.  The information on the batch/lot number for bnt162b2 omi xbb.1.5 has been requested and will be submitted if and when received.