they are still running a low grade temperature of 99.5 F to 101 F.; This is a spontaneous report from a contactable consumer (patient). This consumer reported similar events for two patients. This is a first of two reports.  A 41-year-old female patient received bnt162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE, solution for injection, Batch/Lot Number: EW0183, Expiration Date: unknown), dose 2 via an unspecified route of administration, administered in Arm Right on 14May2021 13:15 (at the age of 41-year-old) as dose 2, 0.3 ml single for COVID-19 immunization. Medical history included ongoing Stomach issues (her stomach issues started about 2 years ago when she had an ulcer), ulcer from an unknown date and unknown if ongoing. Concomitant medication(s) included famotidine (PEPCID [FAMOTIDINE]) taken for stomach issues from an unspecified start date and ongoing (she began taking Pepcid 2 years ago); OMEPRAZOLE taken for stomach issues from an unspecified start date and ongoing (she began taking Omeprazole 2 years ago). Patient previously received first dose of BNT162B2 (solution for injection, Lot Number/Expiry Date: EW0150/Unknown), administered in Arm Right on 22Apr2021 (at the age of 41-year-old) as 0.3 ml for COVID-19 Immunization (History of all previous immunization with the Pfizer vaccine considered as suspect). Patient did not receive additional vaccines administered on same date of the Pfizer suspect. Patient did not receive any vaccinations within 4 weeks prior to the COVID vaccine. Prior vaccinations adverse events were none. Vaccine was not administered at a military facility. Patient said that she and her 19-year-old son both received the 2nd dose of the Pfizer-BioNTech Covid-19 Vaccine on Friday afternoon, 14May2021. As of today, they are still running a low grade temperature of 99.5 F to 101 F. She said they have already went past 24 to 48 hours, and wants to know how long this side effect usually lasts. Reported that she started getting a temperature on Saturday, 15May2021, about 24 hours after she received the COVID-19 vaccine (15May2021 13:15). Again, stated as of today, 17May2021, she was still running a low grade fever of 99.5 to 101. Low grade temperature of 99.5 to 101. Reported that it would seem like she was getting better then all of the sudden the temperature comes back out of nowhere. Reported that she had not been able to get her temperature below 99.5. Reported that she has been doing Tylenol and Motrin and rotating them. (Pharmacy name) brand Ibuprofen, 200 mg tablets; 200 count bottle; Lot Number: 0LE2175A or OLE2175A; Expiry Date: Aug2022; NDC number: 59779-604-82. Reported that she cannot find the bottle of Tylenol. Reported that she knows that it was (Pharmacy name) brand. Reported that she does work in health care and working remotely but wanted to make sure that she was vaccinated before going back to the office. Patient did not visit emergency room and physician office for any adverse event. The patient underwent lab tests and procedures which included temperature: 99.5 to 101 fahrenheit (still running a low grade temperature) on 15May2021. Therapeutic measures were taken as a result of they are still running a low grade temperature of 99.5 f to 101 f. There was no investigation assessment and no relevant tests. The outcome of event was not recovered.; Sender's Comments: Linked Report(s) : US-PFIZER INC-2021557693 Same reporter/drug/AE, different patient