choking experience; throat tickled; dizziness; bowel movements all afternoon which is a common allergic reaction; bowel movements all afternoon which is a common allergic reaction; Her heart started to pound/a rapid heartbeat; her ears started to ring (a pounding in her ears); had pressure in her jaw, chest, head, ears, and allover; high adrenal stimulance; excreted 1 cup of urine more than what she usually does; high pressure; dehydrated; couldn't sleep; This is a spontaneous report from a contactable consumer (patient).  An 80-year-old female patient received the first dose of bnt162b2 (PFIZER-BIONTECH COVID-19 VACCINE, Batch/Lot Number: EN6202), via an unspecified route of administration, administered in Arm Right on 01Mar2021 13:30 (at 80 years old) as single dose for covid-19 immunisation. Medical history included irritable bowel syndrome, allergic to gluten, lecithin, and other barky parts of plants, high pressure, she did not hear very well, left breast surgery, skin cancer. She had a small skin cancer taken off each of her legs, one removed in Jan2020 and one removed in Feb2020. They are all healed up and they are fine, it was not the bad kind. There were no concomitant medications.  The patient experienced choking experience in which her throat tickled, and dizziness, dehydrated, her heart started to pound (a rapid heartbeat), her ears started to ring (a pounding in her ears), she had pressure in her jaw, chest, head, ears, and allover, she had high pressure, excreted 1 cup of urine more than what she usually does, couldn't sleep due to high adrenal stimulance, bowel movements all afternoon which is a common allergic reaction all on 01Mar2021 with outcome of unknown.   Clinical course was reported as follows. She mentioned that she was fine for 20-30 minutes to an hour after she got home. That afternoon, she noticed that her bowel movement was regular, constant, and repeating which was not normal and would typically indicate SIBO (Small intestine bowel overflow) in which the colon empties everything. She mentioned that this was indicative of her gluten allergy. She reported having had bowel movements all afternoon which is a common allergic reaction she has to plants like lectin and gluten especially due to the irritable bowel system-her whole bowel system will empty and she will have to replace 2 days worth of food. With this event starting 01Mar2021 her bowels just kept emptying and emptying. During dinner while she was eating and watching tv, her heart started to pound (a rapid heartbeat), her ears started to ring (a pounding in her ears), she had pressure in her jaw, chest, head, ears, and allover, she had high pressure, and a choking episode in which her throat tickled, and dizziness that she couldn't get up. She took hot water for the tickling sensation and took one aspirin for the other symptoms, but she still did not feel very well. She went to bed at 9pm but couldn't sleep due to high adrenal stimulance, she only slept like 2-3 hours long which she can get from Novocaine with her teeth. She got up 3 times and excreted a cup of urine per time. In the morning, she woke up and excreted 1 cup of urine more than what she usually does. She got herself weighed and had a weight of 109lbs versus the normal 122lbs which indicated that she was really dehydrated so she took her fluids and ate breakfast. Other than this, she mentioned that she got up today and felt fine and feels that in 2 days she will be fine. She felt pretty good and she was going to run but did not dare burn any more calories or fluids so she is sitting still and taking it easy. Regarding outcome of event she reported the pounding pressure like high blood pressure are better, fine# she had a normal breakfast# she can get around and do whatever she needs around the house except she needs now to spend the day recouping from the dehydration so she needs pay attention to what she eats and drinks. She mentions that she runs 3-4 miles a day and tries to be active for her age. She is asking if she can take the 2nd dose in 3 weeks. She is unsure if this is an allergic reaction or something psychological. The outcome of the event was reported as recovering.