a small blister on her arm about 0.5 inch to 1 inch away from the injection site; the site of injection is swollen & tender; the site of injection is swollen & tender/Arm sore; This is a spontaneous report received from a contactable reporter(s) (Pharmacist) from medical information team for a Pfizer sponsored program.  A 36 year-old female patient received bnt162b2 (PFIZER-BIONTECH COVID-19 VACCINE-Solution for injection), administration date 03Aug2021 (Lot number: FC3180) as dose 1, single for covid-19 immunisation. The patient's relevant medical history and concomitant medications were not reported. The following information was reported: BLISTER (non-serious) with onset 04Aug2021, outcome "unknown", described as "a small blister on her arm about 0.5 inch to 1 inch away from the injection site"; VACCINATION SITE SWELLING (non-serious) with onset 04Aug2021, outcome "unknown", described as "the site of injection is swollen & tender"; VACCINATION SITE PAIN (non-serious) with onset 04Aug2021, outcome "unknown", described as "the site of injection is swollen & tender/Arm sore". It was unknown if therapeutic measures were taken as a result of blister, vaccination site swelling, vaccination site pain. Additional information: On question on call, caller stated patient recieved the Pfizer Covid 19 Vaccine around noon time on 03Aug2021. The patient came in today with a small blister on her arm about 0.5 inch to 1 inch away from the injection site. Caller also reports the site of injection is swollen & tender. Caller asking if it's a possible skin reaction & if so do Pfizer have any recommendations for treatment? Responsed with spoke from the PI under, Adverse reactions following the Pfizer-BioNTech COVID-19 Vaccine that have been reported in clinical trials include *injection site pain, * injection site swelling. Revised: 25Jun2021. Spoke from the attached document under "adverse reaction/side effect" in reference to the blister and treatment. "Pharmacist was calling about possible reactions, she was not sure of reporting it, it's for a patient who received the Pfizer-BioNTech COVID-19 Vaccine, first dose yesterday on 03Aug. Transferring agent further stated, "The Pharmacist was calling about, small blisters on the arm, not directly on the injection site but an inch away from the injection site and arm sore and tender, a little swollen and that's it. So she was asking if this was about the reactions on the first dose of the Pfizer-BioNTech COVID-19 Vaccine." Pharmacist stated, "I really just wasn't sure if that was (incomplete sentence), she (Patient) was asking if I knew, if that was a reaction from the vaccine and if so what that blister was and I told her that I wasn't sure but I can see if the manufacturer has any issue or any ideas about any blistering near the injection site."  No follow-up attempts are possible. No further information is expected.  Follow up (04Aug2021): New information received from a Pfizer sponsored program a contactable pharmacist reported for a 36-year-old female patient that includes reporters information, dates for the events, Pfizer-BioNTech COVID-19 Vaccine details, reporters seriousness for Arm sore and tender, a little swollen.  No follow-up attempts are possible. No further information is expected.  Follow-Up (12Aug2021): Follow-up attempts are completed. No further information is expected.