hot flashes; getting "real warm"; Could not walk; Not feeling well; dizzy; This is a spontaneous report from a contactable consumer (patient). A 88-years-old female patient received bnt162b2 (PFIZER-BIONTECH COVID-19 VACCINE, Formulation: Solution for injection, Batch/Lot Number: EM9810, Expiry date was not reported), via an unspecified route of administration, administered in Arm Left on 06Feb2021 11:00 as (at the age of 88-years-old) dose 1, single for COVID-19 immunization. Medical history included thyroid disorder from an unknown date and unknown if ongoing , stevens-johnson syndrome from an unknown date and unknown if ongoing, surgery from an unknown date and unknown if ongoing , rash from an unknown date and unknown if ongoing , ongoing overweight, nephrolithiasis from an unknown date and unknown if ongoing, pain from an unknown date and unknown if ongoing, hypersensitivity from an unknown date and unknown if ongoing, immune system disorder from an unknown date and unknown if ongoing , respiratory disorder from an unknown date and unknown if ongoing. Concomitant medication(s) included levothyroxine (LEVOTHYROXINE) taken for thyroid disorder, start and stop date were not reported; cefalexin monohydrate (KEFLEX [CEFALEXIN MONOHYDRATE]) taken for an unspecified indication from an unspecified start date to 10Feb2021; mirabegron (MYRBETRIQ) taken for an unspecified indication, start and stop date were not reported; duloxetine hydrochloride (CYMBALTA) taken for an unspecified indication, start and stop date were not reported; acetylsalicylic acid (ASPIRINA ADULTOS) taken for an unspecified indication, start and stop date were not reported; meclizine hcl (MECLIZINE HCL) taken for an unspecified indication, start and stop date were not reported. The patient previously took rifampin for infection, vancomycin for infection. Prior Vaccinations, no vaccine within 4 weeks. It was reported that an 88 years old and received the first dose of the Pfizer-BioNTech COVID-19 vaccine on 06Feb2021. She explained feeling "really dizzy" this morning, around 2am. She added having "hot flashes" and getting "real warm" several times. Patient also mentioned she was taking "quite a few pills" and hasn't seen her HCP in a while. She asked if these symptoms were reported side effects of the COVID-19 vaccine. She had been alright, but starting today she was not feeling well, dizzy and could not walk. She asked if these events could be related to the vaccine. Starting on 10feb2021, around 02:00, as far as she was aware, she was in bed and got up and was so dizzy she could not walk. She did not dare try to walk down the hall because she was so wobbly she kept bumping up against the wall. She has a lady who helps her some so she called her thinking she would come and help her; but the lady told her to just go back to sleep. So she got back into bed and went back to sleep and she seems to be ok now; not wonderful, but events are improved. Regarding concomitant products and other medical conditions caller reported yes, lots of them; She was going to start Cephalexin 250mg now, since finished Keflex. Patient was unable to provide any further information on concomitant products or other medical conditions at time of the report other than that documented in formal fields. She was so absent-minded these days that she never knows what was going to happen. She has trouble remembering sometimes. Patient details Include surgical procedures and dates: Lots of allergies. Unknown what those allergies are. She remembers she had Stevens-Johnson syndrome-she got that; she had had breast surgery and they started giving her medication because she developed an infection right away; They gave her Rifampin and Vancomycin and she thinks they overdosed her because she spent 2-3 weeks in the hospital with the Stevens-Johnson syndrome with a rash she developed immediately. She was out of work for a couple of months. Her husband thought she was gonna die but she fooled him. Rifampin: About 2-3 weeks ago she woke in the middle of the night in extreme pain. She called an ambulance which took her away to (hospital name), (city name) where she was for 3 days. She has been taking medication for this. No Family History, she does not think so. Her family been gone so long now. Her mother died of breast cancer and her dad had a heart attack. Patient did not visited Emergency room or not visited physicians office. Patient was not hospitalized. The outcome for all events was unknown.      Follow-up attempts are completed. No further information is expected.