Third dose; site of injection it swelled to about a half size of a golf ball/needle was retracted from the site of the injection, the site was swollen to half the size of a golf ball; Arm was pretty tense/arm was really bent; nodule was still there, it was pretty big, the nodule was a raised area, and when it happened it looked like half a golf ball; This is a spontaneous report received from contactable reporter (pharmacist) from medical information team.  A 39 year-old female patient received BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE), administered in arm right, administration date 22Dec2021 (Lot number: FL3197, Expiration Date: Jun2022) at the age of 39 years as dose 3 (booster), single for COVID-19 immunisation. Relevant medical history included: "Arm was lumpy" (unspecified if ongoing), notes: before administered the drug. There were no concomitant medications. Vaccination history included: Covid-19 vaccine (Dose: 1, Manufacturer Unknown), for COVID-19 Immunization; Covid-19 vaccine (Dose: 2, Manufacturer Unknown), for COVID-19 Immunization. The following information was reported: IMMUNISATION (medically significant) with onset 22Dec2021, outcome "unknown", described as "Third dose"; VACCINATION SITE SWELLING (medically significant) with onset 22Dec2021, outcome "recovering", described as "site of injection it swelled to about a half size of a golf ball/needle was retracted from the site of the injection, the site was swollen to half the size of a golf ball"; LIMB DISCOMFORT (medically significant) with onset 22Dec2021, outcome "unknown", described as "Arm was pretty tense/arm was really bent"; VACCINATION SITE NODULE (medically significant) with onset 22Dec2021, outcome "not recovered", described as "nodule was still there, it was pretty big, the nodule was a raised area, and when it happened it looked like half a golf ball". Therapeutic measures were taken as a result of vaccination site swelling, limb discomfort, vaccination site nodule. Additional information: The patient had the third dose of the Pfizer-BioNTech COVID-19 Vaccine. Pharmacist clarified that she wasn't the one who administered the vaccine. When they retracted the needle from the site of injection it swelled to about a half size of a golf ball. They have put an ice pack on it and has gone down. The reaction was immediate within seconds. It was pretty immediate after the vaccine was administered, and she was called over and said let's apply cold compress right away, then it went down in a few minutes. She said the nodule was still there, it was pretty big, the nodule was a raised area, and when it happened it looked like half a golf ball, she was surprised. The patient was asked if she recalled having reactions to the first two doses and the patient said no. The patient said she didn't have Tylenol, Ibuprofen, or Aspirin prior to getting the vaccine dose. The only treatment done for the lump was just the cold pack. She also noted that the patient's arm was pretty tense and was told to relax her arm. A cold pack was applied to the patient's arm. The patient was told to stop tensing her arm, she kept raising and tensing so she was told to relax the arm, which the patient was doing after getting the vaccine dose. During administration, the patient's arm was really bent, and was advised to relax the arm, and also asked if they took Tylenol, Ibuprofen, or Aspirin, which patient noted they didn't take any medication. Reporter noticed the arm was lumpy before drug was administered. The events were considered serious (Other medically important condition).  No follow-up attempts are possible. No further information is expected.; Sender's Comments: Based on the information provided and plausible temporal association, the causality between BNT162B2 and events cannot be completely excluded.  The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to regulatory authorities, Ethics Committees, and Investigators, as appropriate.