low fever; thyroiditis issue; heart beat was high; he had pain on one side of the neck/stated that he had pain on both sides of his neck; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP) from medical information team for a Pfizer sponsored program.  A 49 year-old male patient received bnt162b2 (BNT162B2), administration date 01Mar2021 (Batch/Lot number: unknown) at the age of 49 years 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: NECK PAIN (non-serious) with onset 08Mar2021, outcome "recovered" (04May2021), described as "he had pain on one side of the neck/stated that he had pain on both sides of his neck"; PYREXIA (non-serious) with onset 25Mar2021, outcome "recovered" (30Apr2021), described as "low fever"; HEART RATE INCREASED (non-serious) with onset 15Mar2021, outcome "recovered" (27Mar2021), described as "heart beat was high"; THYROIDITIS (non-serious) with onset 25Mar2021, outcome "unknown", described as "thyroiditis issue". Relevant laboratory tests and procedures are available in the appropriate section. Therapeutic measures were taken as a result of neck pain, pyrexia, heart rate increased, thyroiditis.  Additional information: Caller stated, "My husband (49 years when he had the vaccine and is 50 years old now) had the 1st Pfizer COVID vaccine on 01Mar2021. 2 weeks after the 1st vaccine, he had pain on one side of the neck, and then he had low fever, heart beat was high. The doctor did an ultrasound and blood test and he thyroiditis issue for the 1st time in his life. We were concerned it was something with the vaccine and he was treated with prednisone. He didn't have the 2nd vaccine due to the issue. We're thinking he might try to get the vaccine. Should he start over again and then take the 2nd one again. Caregiver calling for her husband who received his first dose of Pfizer COVID vaccine at age 49 on 01Mar2021. Stated that two weeks after first dose he had pain on the side of his neck, low fever and his heartbeat was high. Stated that the doctor did an ultrasound and blood test and he was diagnosed with thyroiditis. Stated that that this was the first time that he had this in his life. Stated that she is concerned that this had something to do with vaccine. Stated that he was treated with Prednisone. Reporter stated that he got better from the pain on the right side of his neck after the Prednisone on 27Mar2021. Stated the pain went away. Stated that after three weeks of taking Prednisone that the pain came back again on both sides of his neck on 26Apr2021 which she later clarified as 21Apr2021. Stated that on 26Apr that he had a CT, ultrasound and blood tests. Later clarified that on 21Apr2021 that after lowering the Prednisone that the pain on his neck came back on both sides. Stated that he was placed back on Prednisone at a high dose for two more weeks starting on 28Apr2021 and it got better. Stated that on 25Apr2021 that he had a low grade fever and then a had it went to a high fever on 27Apr2021 and it resolved completely on 30Apr. Stated that he recovered after he was placed back on Prednisone at a high dose. Stated that he was diagnosed with thyroiditis on 25Mar2021 and got better on 27Mar2021. Later clarified that first thyroid test was on 21Mar and his thyroid was hypo. Stated that the thyroid blood test went to hyper and now is hypo. Stated that he was taking Prednisone and it got better. Multiple attempts made to redirect caller; unable to clarify details with the caller. Treatment: Stated that he took Tylenol for fever. Stated that heartbeat was high and got better when he started taking Prednisone. Reporter clarifies after the first dose, two weeks later he had thyroiditis, when the thyroid goes hyper. He wants to have the vaccine, and she just wants her question answered whether he needs to get the second dose or start over since she knows it is supposed to be 21 days in between doses.  The lot number for bnt162b2 was not provided and will be requested during follow up.