She said maybe she is experiencing a drug interaction between the antibiotic and the COVID-19 Vaccine; woke up early this morning with a rash from head to toe, saying the rash is really itchy; she had big, red welts when she first woke up this morning; This is a spontaneous report from a contactable consumer reporting for herself. A 62-year-old female patient received first dose of bnt162b2 (BNT162B2, lot number: EL1283, expiry date: not reported), via an unspecified route of administration, on 11Jan2021 12:00PM at a single dose on deltoid, right for COVID-19 immunization. Vaccination Facility Type was clinic facility. The patient also took sulfamethoxazole, trimethoprim (BACTRIM, tablet, lot number and expiry date were not reported), oral, from an unspecified date and ongoing, at 1 DF, 2x/day for urinary tract infection (UTI). She was prescribed 10 sulfamethoxazole, trimethoprim tablets, and has been taking 1 tablet by mouth, twice a day. She said she was prescribed a 5-day treatment course, and she has 1 dose left at the time of report, 14Jan2021. Medical history included colon cancer from 2018, sigmoid colon and part of her descending colon were removed, septic shock, ureter was severed, colostomy, nephrostomy, ileostomy, frequent UTIs, bowel obstruction, several stents placed in her colon due to the strictures, coded in the ICU, was on a ventilator, sigmoidoscopy, anemic from an unspecified date to an unspecified date (does not have a problem with anemia anymore), blood transfusions, was in the hospital for a week at the end of Jul2020 to an unspecified date. She reported she had colon cancer 2 years ago that was 1 encapsulated tumor, so she didn't need chemo or radiation. She said her sigmoid colon and part of her descending colon were removed. She had severe complications after the surgery: her resection ruptured, she had septic shock and her ureter was severed. She had a colostomy and nephrostomy at the same time and then an ileostomy after the colostomy was taken down. She has frequent UTIs due to no backflow valve from her ureter to her kidney. She said she has had so much work on her colon, she has constant strictures resulting in bowel obstructions. She said she has had several stents placed in her colon due to the strictures. She said she didn't know if her previous medical history has anything to do with the rash she is experiencing now. She said when she had septic shock, she coded in the ICU and was on a ventilator. No further details provided. Reported she had a COVID-19 test done in Nov2020 prior to having a follow-up sigmoidoscopy at the hospital. She said her primary care doctor set her up to have a thyroid panel, CBC, and lipid panel done, and she will going to have those tests shortly. She said she had daily blood tests performed when she was in the hospital for a week in Oct2020, and when she was in the hospital for a week at the end of Jul2020. She said all her blood work was fine during those hospital stays. No further details provided. She was anemic in the past due to her colon cancer, but she does not have a problem with anemia anymore. She said at one point her red blood cells were down to 6.4 and she needed to get blood transfusions. Concomitant medications were none. The patient previously received a flu vaccine in Oct2020. The patient did not have other vaccinations within 4 weeks prior to receiving bnt162b2. The patient reported she had the COVID-19 Vaccine on Monday, 11Jan2021, in the afternoon, clarified as 12:00PM. She had to wait 20-30 minutes after receiving her first COVID-19 Vaccine dose to make sure she had no reaction. She woke up early this morning (14Jan2021) with a rash from head to toe, saying the rash is really itchy. She had big, red welts when she first woke up this morning. She said she is not experiencing any pain, fever, or anything else. She said she has had no reactions to vaccines before. She is wondering if it makes any difference, but she had a UTI prior to taking the COVID-19 Vaccine. She said she has been taking antibiotics for the UTI. She said maybe she is experiencing a drug interaction between the antibiotic and the COVID-19 Vaccine, and that could have contributed to her rash. She first noticed the head to toe rash this morning. She said she initially woke up at 4:30AM and had a bowl of cereal. She said at that time she didn't notice anything different and went back to bed. When she woke up later on, and looked in the mirror, she saw she was covered in a rash. She had a scheduled video conference with her doctor yesterday, 13Jan2021, and her doctor is unaware that she developed a rash since then. Her rash doesn't look as red as when she first woke up this morning. She said she dare says that the rash possibly improved a little. She said there are no big, red welts like when she first woke up this morning. She said she can live with the rash but wants to know if she still can get her second COVID-19 Vaccine dose. Her second COVID-19 Vaccine dose is scheduled on 01Feb2021. She said she wants to know if the rash is going to prevent her from getting the second COVID-19 Vaccine dose. She said she is terrified of getting the COVID-19 Virus. She said her husband wouldn't survive if he got the COVID-19 Virus. She asked if a rash is common after receiving the COVID-19 Vaccine, and if the rash will go away on its own. The action taken in response to the events for sulfamethoxazole, trimethoprim was unknown. The patient did not receive any corrective treatment for the reported adverse events. She has considered taking an antihistamine but was going to wait until she finishes her coffee to see how she feels. She clarified at the end of the call that her rash was not as bad as when she first noticed it, saying the rash is getting a little better. The adverse events did not require emergency room or physician office visit. Outcome of the events was recovering.