Ipsilateral axillary lymphadenopathy.; a firm, swollen, and mildly uncomfortable swelling under armpit (same arm as injection).; Swelling increased to the size of a golf ball by 48 hours post-dose before gradually disappearing by Day 5 post-dose; mild fatigue; muscle soreness; Injection site pain was mild but apparent through 3 days post-dose.; booster; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP). The reporter is the patient.  A 27 year-old male patient received bnt162b2 (BNT162B2), intramuscular, administered in arm left, administration date 08Oct2021 (Lot number: FE3592) at the age of 27 years as dose 3 (booster), single for covid-19 immunisation. Relevant medical history included: "hypertension" (unspecified if ongoing), notes: Primary longstanding hypertension .; "obesity" (unspecified if ongoing), notes: obesity; "headaches" (unspecified if ongoing). Concomitant medication(s) included: BENAZEPRIL/HCTZ; IBUPROFEN taken for headache. Vaccination history included: Bnt162b2 (Dose Number: 2, Batch/Lot No: EP7533, Location of injection: Arm Left, Route of Administration: Intramuscular), administration date: 03Apr2021, when the patient was 26 years old, for COVID-19 immunization; Bnt162b2 (Dose Number: 1, Batch/Lot No: EN6202, Location of injection: Arm Left, Route of Administration: Intramuscular), administration date: 06Mar2021, when the patient was 26 years old, for COVID-19 immunization. The following information was reported: IMMUNISATION (non-serious) with onset 08Oct2021, outcome "recovered", described as "booster"; LYMPHADENOPATHY (non-serious) with onset 09Oct2021, outcome "recovered", described as "Ipsilateral axillary lymphadenopathy."; SWELLING (non-serious) with onset 09Oct2021, outcome "recovered", described as "a firm, swollen, and mildly uncomfortable swelling under armpit (same arm as injection)."; CONDITION AGGRAVATED (non-serious) with onset 09Oct2021, outcome "recovered", described as "Swelling increased to the size of a golf ball by 48 hours post-dose before gradually disappearing by Day 5 post-dose"; FATIGUE (non-serious) with onset 09Oct2021, outcome "recovered", described as "mild fatigue"; MYALGIA (non-serious) with onset 09Oct2021, outcome "recovered", described as "muscle soreness"; VACCINATION SITE PAIN (non-serious) with onset 09Oct2021, outcome "recovered", described as "Injection site pain was mild but apparent through 3 days post-dose.". Therapeutic measures were not taken as a result of immunisation, lymphadenopathy, swelling, condition aggravated, fatigue, myalgia, vaccination site pain. Additional information: The patient received vaccine at pharmacy or drug store. Ipsilateral axillary lymphadenopathy. 24 hours after immunization, the patient noticed a firm, swollen, and mildly uncomfortable swelling under armpit (same arm as injection). Swelling increased to the size of a golf ball by 48 hours post-dose before gradually disappearing by Day 5 post dose. Patient also experienced mild fatigue and muscle soreness between 12 and 48 hours post-dose. Injection site pain was mild but apparent through 3 days post-dose.  Follow-up attempts are completed. No further information is expected.