some possible increase in heat exhaustion; The caller reports this was kind of like a heat stroke; Unable to get through exercises after receiving the Pfizer Covid Vaccine; This is a spontaneous report received from a contactable reporter(s) (Physician) from medical information team for a Pfizer sponsored program.  A 30 year-old male patient received bnt162b2 (BNT162B2), administration date 03Jun2021 10:04 (Lot number: EW0180) at the age of 30 years as dose 2, single for covid-19 immunisation. The patient had no relevant medical history. The patient's concomitant medications were not reported. Vaccination history included: Bnt162b2 (Dose:1, lot: EW0175, Route of admin : Deltoids alternating , time-08:47), administration date: 12May2021, when the patient was 30 years old, for Covid-19 immunization. The following information was reported: HEAT EXHAUSTION (non-serious), outcome "recovering", described as "some possible increase in heat exhaustion"; HEAT STROKE (non-serious), outcome "recovering", described as "The caller reports this was kind of like a heat stroke"; EXERCISE TOLERANCE DECREASED (non-serious) with onset 11Jun2021, outcome "recovering", described as "Unable to get through exercises after receiving the Pfizer Covid Vaccine". The event "unable to get through exercises after receiving the pfizer covid vaccine" was evaluated at the physician office visit and emergency room visit. Relevant laboratory tests and procedures are available in the appropriate section.  Additional information: The patient did not receive any other vaccine on same date with the Pfizer vaccine considered as suspect. The reporter confirmed that no other vaccines were given within 14 days, not sure about 4 weeks. There were no adverse events reported following prior vaccinations. There is no family medical history reported. The reporter reported that some of his men were actually experiencing some difficulty in carrying out there usual exercises as compared to before. He mentioned some possible increase in heat exhaustion but he is not positive that it is caused by the vaccine. In line with this, he would like to have some information in regards precaution that may be aware of regarding an increase in heat exhaustion after "x" amount of days after getting the vaccine. Over-all there were 28 people reporting this side effect after getting their second dose on 06Jun2021. But demographics given were only for 4 people. All male aged 20 years, 30 years, 22 years and 24 years old respectively. History: No, generally most of people here have same kind of thing as far as labs go. The patient had an elevated CK of 189 on 11Jun2201. A really mild AKI of 1.3. Both the CK and AKI normalized or were down trending on 16Jun2021. There are adverse events that may not have occurred in the clinical trial, but may have occurred in the 'real-world' post-authorization setting. Pfizer cannot provide treatment recommendations. However, the CDC has established a project comprised of a team of vaccine safety experts who can be consulted on complex COVID-19 vaccine safety questions The reporter clarified that he has gotten through 4 patients of the 28 patients and is slowly working his way through interviewing the patients.  The reporter wanted to get started and figure out whether Pfizer is seeing anything else.  Follow-up attempts are completed. No further information is expected.; Sender's Comments: Linked Report(s) : US-PFIZER INC-2021755866 Same reporter/ drug/ AE, different patient