Interrupted his sleep; Stuff in his throat/weird stuff on his throat; Cough; weird stuff on his throat; Rapid heart rate; really bad chest pains; vomit; nausea; gasping for air; Neck spasms; Blood pressure, clarified as low blood pressure; It was like he was catching pneumonia but then his nose was running,; severe congestion, like bad stuff in his chest and lungs; severe allergies; tired; he got really sick; It was like he was catching pneumonia but then his nose was running,; This is a spontaneous report from a contactable consumer (patient) via Medical Information Team and from a Pfizer sponsored program. A 44-years-old male patient received the first dose of BNT162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE; formulation: Solution for injection, Lot Number: EW0167, Expiry date: UNKNOWN, NDC number: Unknown), via an unspecified route of administration at the right arm on 29May2021 11:15 as a SINGLE DOSE for covid-19 immunization. Medical history included myocardial infarction from an unknown date and unknown if ongoing, illness from Feb2020 to an unknown date, whole family was sick in February, palpitations from an unknown date and unknown if ongoing. History and investigation included "he said he had nothing to add during that time. But about a year ago he had gone to the emergency room for a heart attack scare. he thought, because this was when COVID first started happening, his whole family was sick in February and they would not test them at that time because they had not been to China and they never found out if they had it but he ended up getting tested for COVID when he was sick like 6 months later and then that went away and he started having heart palpitations and then after that he thought he would get a COVID antibody test and that came back negative, they told him by the time he got the antibody test, they told him he could have had it but it is not showing up on their antibody rapid test thing. He confirms this all occurred last year in 2020, he thinks it was almost a year ago. He would be sitting on the couch and his heart started racing like crazy. He did not know what that was all about". He said he had no discomfort at all. Concomitant medications were not reported. On an unspecified date in 2021 patient experienced it was like he was catching pneumonia but then his nose was running, neck spasms, blood pressure, clarified as low blood pressure, tired, he got really sick, severe congestion, like bad stuff in his chest and lungs, it was like he was catching pneumonia but then his nose was running, on an unspecified date in 2021 severe allergies, on 29May2021 rapid heart rate, really bad chest pains, stuff in his throat/weird stuff on his throat , cough, on an unspecified date in May2021 vomit, nausea, on an unspecified date in May2021, gasping for air, on an unspecified date interrupted his sleep. Caller received his first dose and was experiencing symptoms such as rapid heart rate and neck spasms and blood pressure. He was too tired to go to the emergency room. He had the weird cough and also stated he had weird stuff on his throat and severe allergies. Regarding his second dose, he wanted to receive but he wanted to know if he could receive a half dose. He also had really bad chest pains and he was going to go to the emergency room but he was too tired to even go. The other reason for calling, he was trying to find out because he was afraid to take the second dose, he wanted to know if he could take a half dose or something, he was trying to find out what he should do. Severe allergies, caller clarified it was like severe allergies or like hay fever kind of, but it was different. Rapid heart rate: He said this began happening the same day as the dose was given, 29May2021, 4 hours after he got the shot. It was not ongoing, it lasted about a day. The rapid heart rate went away the next morning, it stopped doing the crazy things it was doing the next morning, 30May2021. He confirmed that has recovered completely. The chest pain coincided with the rapid heart rate. It went way the same time as the rapid heart rate. It seemed like they both would come and go until the next morning, He confirmed that had recovered completely. He said then the low blood pressure was going on too. It was like it interrupted his sleep, he did not know how to explain it, like he had low blood pressure or like his heart would stop beating and he would wake up gasping for air. It was kind of like a nauseous feeling, he wanted to vomit. It happened with the low blood pressure and was mostly when he was sleeping and a little through the day, the nausea he means, it lasted about a day and a half. The nausea went away on the 30May or the 31May he cannot remember for sure. The cough and stuff in his throat began at the same time the heartbeat stuff started and the cough went away after 2 days. He felt pretty good for about 3 days and then he got really sick, with severe congestion, like bad stuff in his chest and lungs. It was like he was catching pneumonia but then his nose was running, it felt weird like a sickly poison kind of feeling like after he got the shot, he could not tell but it seemed like severe allergies or like hay fever kind of but it was different, it was a weird feeling. He had taken a bunch of herbal remedies Benadryl took herbal allergy stuff and it worked really fast and after like 3 days it was gone. He does not know what that was but it was pretty intense. No further information provided. It was reported that, caller got his first dose of the Pfizer Covid-19 vaccine on 29MAY2021 and had side effects. He wanted to know if he could get only a half dose of the COVID-19 vaccine. He also wanted to know if there was any correlation to having COVID-19 and having more of a reaction. Caller wanted to know if there was a correlation between having COVID-19 and having more side effects to the vaccine. He stated that his Pharmacist said there might be a correlation to people having COVID before getting the vaccine and having more problematic side effects from the first vaccine instead of the second. Response was given as "he should not get the Pfizer-BioNTech COVID-19 Vaccine if he had a severe allergic reaction after a previous dose of the vaccine or if he had a severe allergic reaction to any ingredient of the vaccine. The decision to receive the second dose for any other reason cannot be made by Pfizer. He was referred to speak to healthcare provider about the risks of the vaccine compared to the risks of potentially not being fully protected against COVID-19 infection. Healthcare provider would have known the health situation and could access to information that better help inform the decision. From the CONS document on efficacy. Two shots were generally needed to provide the best protection against COVID-19 and the shots were given several weeks apart. The first shot primes the immune system, helping it recognize the virus, and the second shot strengthens the immune response. Side effects after the second shot might be more intense than the ones experienced after the first shot. The side effects are normal signs that body is building protection and should go away within a few days". The patient underwent lab tests and procedures which included sars-cov-2 antibody tested negative. Therapeutic measures were taken as a result of severe allergies (drug hypersensitivity). He visited emergency room due to the event chest pain. On an unspecified date in 2021 the outcome of the events it was like he was catching pneumonia but then his nose was running, neck spasms, blood pressure, clarified as low blood pressure, tired, he got really sick, severe congestion, like bad stuff in his chest and lungs, it was like he was catching pneumonia but then his nose was running was unknown, on an unspecified date in 2021, severe allergies was recovered, rapid heart rate, really bad chest pains, cough was recovered on 30May2021, on an unspecified date in May2021 vomit, nausea was recovered, gasping for air, interrupted his sleep and stuff in his throat/weird stuff on his throat was unknown.  Information on the lot/batch was available, Additional information has been requested.