arm sensitive/ had tenderness; every muscle in body was bothering patient/ muscle problems; leg cramps; very tired; headache; sore throat; polymyalgia rheumatica; This is a spontaneous report received from contactable reporter(s) (Consumer or other non HCP) from medical information team. The reporter is the patient.  A 75-year-old female patient received bnt162b2 (BNT162B2), on 23Mar2021 as dose 2, single (Lot number: ER8727) at the age of 75 years, in left arm for covid-19 immunisation. The patient's relevant medical history included: "Hashimoto's" (ongoing); "Fibromyalgia" (ongoing); "Sjogren's" (ongoing); "back surgery" (unspecified if ongoing). The patient's family history included: "Rheumatoid arthritis" (ongoing), notes: in her late 30s. Doctor tried to figure out if it was rheumatoid arthritis or Lupus. Patient's aunt had rheumatoid arthritis. There were no concomitant medications. Vaccination history included: bnt162b2 (1st dose, lot: EN6205, Anatomical location: Upper left arm, Time: Unknown, sometime in morning), administration date: 02Mar2021, when the patient was 75-year-old, for Covid-19 immunization, reaction(s): "arm irritation, had tenderness". The following information was reported: POLYMYALGIA RHEUMATICA (medically significant) with onset Mar2021, outcome "not recovered"; PAIN IN EXTREMITY (non-serious), outcome "unknown", described as "arm sensitive/ had tenderness"; MUSCLE DISORDER (non-serious), outcome "unknown", described as "every muscle in body was bothering patient/ muscle problems"; MUSCLE SPASMS (non-serious), outcome "unknown", described as "leg cramps"; FATIGUE (non-serious), outcome "unknown", described as "very tired"; HEADACHE (non-serious), outcome "unknown"; OROPHARYNGEAL PAIN (non-serious), outcome "unknown", described as "sore throat". Therapeutic measures were taken as a result of pain in extremity, muscle disorder, muscle spasms, fatigue, headache, oropharyngeal pain.   Clinical course: Patient had no other vaccinations within four weeks prior to the first administration date of the Pfizer COVID-19 vaccines. Clarified and confirmed patient had all of the Pfizer COVID-19 vaccines. Had the usual arm irritation, was very mild, with 1st dose on 02Mar2021. With 2nd dose on 23Mar2021 (Time: Unknown, sometime in morning), reaction was more severe, affected muscles, leg cramps, very tired, every muscle in body was bothering patient. Doctor provided medication, Prednesol, and it did help, prescribed on 30Mar2021. Triggered another autoimmune disease in body, polymyalgia rheumatica, as of Mar2021. In between had muscle problems, so took the medication again. Something puzzling patient, doesn't know if connected, but possible, but with every dose of the vaccine patient has had muscle problems. Start date of arm irritation: Unknown, stating was arm sensitive with 1st dose or 2nd dose, not sure, maybe, stating every one says that, could have had arm irritation with 1st dose, had tenderness, got progressively worse. Also had a headache and sore throat with 2nd dose as well. The autoimmune disease Polymyalgia Rheumatica was triggered by the vaccine, according to rheumatologist. Patient stated patient would rather have these events than the disease itself. Patient height: Shrunk form back surgery, probably 5 feet 3 inches. Patient weight: Unknown patient stated because of the Prednesol medication, maybe 165 pounds.  The information on the batch/lot number for [BNT162B2] has been requested and will be submitted if and when received.; Sender's Comments: Linked Report(s) : US-PFIZER INC-202300337361 same patient/vaccine, different doses/event.;