booster; Clarifies she got AstraZeneca covid vaccine first and second dose since she was in a clinical study for covid vaccine and she wanted to ask if it was safe to mix and get the Pfizer covid booster; Clarifies she got AstraZeneca covid vaccine first and second dose since she was in a clinical study for covid vaccine and she wanted to ask if it was safe to mix and get the Pfizer covid booster; under armpit is swollen; allergic reaction; Swelling of the lymph nodes; 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 64 year-old female patient received bnt162b2 (BNT162B2), administered in arm left, administration date 10Dec2021 12:00 (Lot number: 331308A) at the age of 64 years as dose 3 (booster), single for covid-19 immunisation. Relevant medical history included: "high blood pressure" (unspecified if ongoing), notes: diagnosed about 10 years ago; "vertigo at one time and was told she had low potassium" (unspecified if ongoing); "vertigo at one time and was told she had low potassium" (unspecified if ongoing); "has to get her magnifying glass to read her vaccination card" (unspecified if ongoing), notes: has to get her magnifying glass to read her vaccination card; "lymph nodes were swollen" (unspecified if ongoing), notes: She was in the emergency room last month for lymph node and pelvic infection (prior to getting Pfizer covid booster), she felt like her whole insides where swollen out, she had a cat scan and was told they saw pelvic and lymph nodes were swollen. She was not admitted to the hospital.; "pelvic and lymph nodes were swollen" (unspecified if ongoing), notes: She was in the emergency room last month for lymph node and pelvic infection (prior to getting Pfizer covid booster), she felt like her whole insides where swollen out, she had a cat scan and was told they saw pelvic and lymph nodes were swollen. She was not admitted to the hospital.; "pelvic infection" (unspecified if ongoing), notes: She was in the emergency room last month for lymph node and pelvic infection (prior to getting Pfizer covid booster), she felt like her whole insides where swollen out, she had a cat scan and was told they saw pelvic and lymph nodes were swollen. She was not admitted to the hospital.; "crooked fingers" (unspecified if ongoing), notes: Reports she has arthritis in her left hand and she had crooked fingers, fingers were starting to turn and after the first dose it straightened her fingers out. Concomitant medication(s) included: HYDROCHLOROTHIAZIDE taken for hypertension (ongoing); POTASSIUM CHLORIDE taken for vertigo, blood potassium decreased (ongoing). Vaccination history included: Azstrazeneca (Dose: 1, Lot: AQ3324 (the Q looks like a zero with a line through it, asks if it is a q) or it could AO3324), administration date: 19Nov2020, when the patient was 63 years old, for COVID-19 immunization, reaction(s): "she felt like a whole mac truck hit her body"; Azstrazeneca (Dose: 2, Lot: AQ3324 (the Q looks like a zero with a line through it, asks if it is a q)), administration date: 18Dec2020, when the patient was 64 years old, for COVID-19 immunization; Azstrazeneca (Dose: 1, Lot: AQ3324 (the Q looks like a zero with a line through it, asks if it is a q) or it could AO3324), administration date: 19Nov2021, when the patient was 63 years old, for COVID-19 immunization, reaction(s): "The next day she had a bad earache", "migraine headache", "then the next day it hit her respiratory system", "she has arthritis in her left hand", "fingers were starting to turn and after the first dose it straightened her fingers out."; Flu shot (Prior Vaccinations (within 4 weeks): Flu and pneumonia shot one month (in Oct2019) prior to AstraZeneca first dose of the covid vaccine), administration date: Oct2019, for immunization; Pneumonia shot (Prior Vaccinations (within 4 weeks): Flu and pneumonia shot one month (in Oct2019) prior to AstraZeneca first dose of the covid vaccine), administration date: Oct2019, for immunisation. The following information was reported: IMMUNISATION (non-serious) with onset 10Dec2021, outcome "unknown", described as "booster"; OFF LABEL USE (non-serious), INTERCHANGE OF VACCINE PRODUCTS (non-serious) all with onset 10Dec2021, outcome "unknown" and all described as "Clarifies she got AstraZeneca covid vaccine first and second dose since she was in a clinical study for covid vaccine and she wanted to ask if it was safe to mix and get the Pfizer covid booster"; PERIPHERAL SWELLING (non-serious) with onset Dec2021, outcome "not recovered", described as "under armpit is swollen"; HYPERSENSITIVITY (non-serious) with onset Dec2021, outcome "unknown", described as "allergic reaction"; LYMPHADENOPATHY (non-serious) with onset Dec2021, outcome "unknown", described as "Swelling of the lymph nodes". Relevant laboratory tests and procedures are available in the appropriate section. Therapeutic measures were taken as a result of peripheral swelling, hypersensitivity, lymphadenopathy. No follow-up attempts are possible. No further information is expected.