legs swelled 2x the size up; could hardly walk; could not sleep; extreme joint pain; This is a spontaneous report received from contactable reporter(s) (Consumer or other non HCP) from medical information team for a Pfizer sponsored program. The reporter is the patient.  A 73 year-old female patient received bnt162b2 (BNT162B2), administration date 27Feb2021 (Lot number: EN6198, Expiration Date: 30Jun2021) at the age of 73 years as dose 2, single for covid-19 immunisation. Relevant medical history included: "Arthritis" (ongoing); "Psoriatic arthritis", start date: 2001 (unspecified if ongoing), notes: Diagnosed Around 2001, Psriatic Arthritis With Osteoarthritis.; "OSTEOARTHRITIS", start date: 2001 (unspecified if ongoing), notes: Diagnosed Around 2001, Psriatic Arthritis With Osteoarthritis. Concomitant medication(s) included: METHOTREXATE taken for psoriatic arthropathy (ongoing). Past drug history included: Clindamycin, reaction(s): "allergic to clindamycin"; Levaquin, reaction(s): "allergic to Levaquin"; Humira, reaction(s): "did not do anything"; Otezla, reaction(s): "did not do anything". Vaccination history included: Bnt162b2 (Dose 1, Single, Lot number: EL9262, Expiry Date: 31May2021), administration date: 05Feb2021, when the patient was 73 years old, for Covid-19 immunization, reaction(s): "diarrhea", "vomiting". The following information was reported: PERIPHERAL SWELLING (non-serious) with onset 27Feb2021, outcome "recovered" (May2021), described as "legs swelled 2x the size up"; GAIT DISTURBANCE (non-serious) with onset 27Feb2021, outcome "recovered" (May2021), described as "could hardly walk"; INSOMNIA (non-serious) with onset 27Feb2021, outcome "recovered" (May2021), described as "could not sleep"; ARTHRALGIA (non-serious) with onset 27Feb2021, outcome "recovered" (May2021), described as "extreme joint pain". The events "legs swelled 2x the size up", "could hardly walk", "could not sleep" and "extreme joint pain" were evaluated at the physician office visit. Relevant laboratory tests and procedures are available in the appropriate section.  Additional information: After 1st dose, the patient experienced diarrhea and vomiting. On her 2nd dose, her legs swelled 2x the size up and experienced extreme joint pain. She experienced this for a long time. Asked if it was possible that transport medium of the booster dose would be different from the second shot that she took. She stated that friend said that she was not allergic to the vaccine, and it might be from the transport media. She also suggested that if we need a copy of her MRI result, she would be happy to send it to Pfizer for updates. she received first dose of Pfizer Covid vaccine on 05Feb2021 and after that dose she experienced a little bit of diarrhea and vomiting. On 27Feb2021, she got second dose of the vaccine and she said her leg instantly swelled up and were pretty swollen. She has allergies to clindamycin and Levaquin and said her doctor told her that she probably did not have an allergic reaction to the vaccine because of her swollen legs but something was mentioned about transport medium, and she wants more information about this. She clarified that the doctor was absolutely useless when it came with anything with the vaccine, she called her friend who worked for something to do with vaccines and mentioned she may be allergic to a transport medium within the vaccine. She stated that her leg swelling was miserable, extreme joint pain, could hardly walk. After first dose, later that night the symptoms started, and she was fine by 5 the next morning. After second dose, that night she started swelling until her legs were double in size, it was hurting so bad she had to scream, could not sleep, states she finally slept crunched over in chair. States improved gradually over three months; she was basically cleared by end of May2021. Exact dates unknown. Her husband was tired and a little temperature after his first dose, 1temperature was 101 that he recalls but it disappeared, went to the () and had his there. She really wants to get the booster vaccine, but she was scared that it may happen again and wants to get information about the transport mediums that may be in the vaccine. If this was a reaction to them, should she not get the booster. She has taken Humira and otezla before and they did not do anything was on this prior to covid shot, said it was a waste of money, takes a little bit of time to get out of system. No product information on hand at this time. She used to be a (occupation). Got the vaccines at the (Location Withheld), states she used to work there. States she did have an MRI, no exact details known at this time. Patient Ethnicity: (Race Withheld). Reporter email: (Withheld). HCP DETIALS: Dr (Name Withheld), rheumatologist, and Occupation/Specialty: Primary. No further contact details provided. Covid vaccine was a Pfizer product. Investigation Assessment was no. There was a Product Complaint.  No follow-up attempts are possible. No further information is expected.