because of this I've had to reduce to only working one day a week; This has prevented me from performing normal daily functions; neurological issues; felt like she was going to faint; chronic abdominal digestive issues gotten worse/side effects have progressed to really bad; difficulty breathing; really bad head pain in back of head; tail bone pain; brain fog; difficulty focusing; blurry vision slightly; hasn't been driving; chronic abdominal digestive issues gotten worse and heartburn; chronic abdominal digestive issues gotten worse and heartburn; muscle fatigue; I have had joint pain/joint pain in fingers, knees and ankles; swelling; This is a spontaneous report received from contactable reporter(s) (Consumer or other non HCP and Physician) from medical information team for a Pfizer sponsored program. The reporter is the patient. Other Case identifier(s): MIQ-02032022-344.  A 26 year-old female patient received bnt162b2 (COMIRNATY), intramuscular, administered in deltoid left, administration date 30Aug2021 12:09 (Lot number: FD0809) at the age of 26 years as dose 1, single for covid-19 immunisation. Relevant medical history included: "Chronic Digestive Issues" (ongoing), notes: Started about 10 Years Ago and haven't really been diagnosed; "Allergic to Shellfish" (ongoing); "Irritable bowel syndrome" (ongoing); "Dyspepsia", start date: 2013 (ongoing); "GERD" (unspecified if ongoing). Concomitant medication(s) included: PANTOPRAZOLE taken for gastrooesophageal reflux disease, dyspepsia, start date: 15Jul2021. The following information was reported: ARTHRALGIA (non-serious) with onset 02Sep2021, outcome "not recovered", described as "I have had joint pain/joint pain in fingers, knees and ankles"; LOSS OF PERSONAL INDEPENDENCE IN DAILY ACTIVITIES (non-serious), outcome "unknown", described as "This has prevented me from performing normal daily functions"; NERVOUS SYSTEM DISORDER (non-serious), outcome "unknown", described as "neurological issues"; MUSCLE FATIGUE (non-serious) with onset 02Sep2021, outcome "not recovered", described as "muscle fatigue"; IMPAIRED WORK ABILITY (non-serious), outcome "unknown", described as "because of this I've had to reduce to only working one day a week"; HEADACHE (non-serious) with onset 30Jan2022, outcome "not recovered", described as "really bad head pain in back of head"; BONE PAIN (non-serious) with onset 30Jan2022, outcome "not recovered", described as "tail bone pain"; FEELING ABNORMAL (non-serious) with onset Jan2022, outcome "not recovered", described as "brain fog"; DISTURBANCE IN ATTENTION (non-serious) with onset Jan2022, outcome "not recovered", described as "difficulty focusing"; VISION BLURRED (non-serious) with onset Jan2022, outcome "not recovered", described as "blurry vision slightly"; GASTROINTESTINAL DISORDER (non-serious), DYSPEPSIA (non-serious) all with onset Dec2021, outcome "not recovered" and all described as "chronic abdominal digestive issues gotten worse and heartburn"; PRESYNCOPE (non-serious), outcome "not recovered", described as "felt like she was going to faint"; IMPAIRED DRIVING ABILITY (non-serious) with onset Jan2022, outcome "not recovered", described as "hasn't been driving"; CONDITION AGGRAVATED (non-serious), outcome "unknown", described as "chronic abdominal digestive issues gotten worse/side effects have progressed to really bad"; SWELLING (non-serious) with onset 02Sep2021, outcome "unknown", described as "swelling"; DYSPNOEA (non-serious), outcome "unknown", described as "difficulty breathing". The event "i have had joint pain/joint pain in fingers, knees and ankles" was evaluated at the emergency room visit. Relevant laboratory tests and procedures are available in the appropriate section. Therapeutic measures were taken as a result of arthralgia, loss of personal independence in daily activities, nervous system disorder, muscle fatigue, impaired work ability, headache, bone pain, feeling abnormal, disturbance in attention, vision blurred, gastrointestinal disorder, dyspepsia, presyncope, impaired driving ability, condition aggravated, swelling.  Additional information: It was reported that the patient experienced joint pain in fingers, knees and ankles, really bad head pain in back of head, tail bone pain, brain fog, difficulty focusing, blurry vision slightly, hasn't been driving, muscle fatigue, chronic abdominal digestive issues gotten worse and heartburn, felt like she was going to faint, back pain, chest pain, difficulty breathing which were worsened except neurological issues and prevented her from performing normal daily functions and because of this she had to reduce to only working one day a week. She stated that it had been 6 months, and she had to see a rheumatologist and neurologist, and she still had joint pain and her side effects have progressed. Stated that she had an MRI taken the other day and the doctors are clueless right now on what to do. Caller stated that neurologist recommend her to go on an antidepressant to see if it was a nerve issue to calm her nerves down and stated that her rheumatologist wants her to try an anti-seizure medication called gabapentin where the events brain fog, fatigue, chest pain started on gabapentin. She was kept on prednisone on 3Oct2021, it was the general pack of prednisone and she didn't felt much different, but when she stopped taking it, she felt like a truck hit her and she was in a lot of pain. Since the rheumatologist thought the prednisone helped a bit, he upped the dosage to 10mg (NDC: 0054-0017-25 Lot: AB4663A Expiration: May2023) and she had to take it again on 16Nov2021 and that was when she had a lot of side effects from the Prednisone she was on it for a week and a half. Caller stated that she went to the emergency room for the Joint Pain on 24Oct2021 and on 24Nov2021 for prednisone reaction and they said to cut the prednisone cold turkey and the next week she struggled with getting back to normal. No additional vaccines were administered on same date of the Pfizer suspect. The patient had received no Prior Vaccinations (within 4 weeks) and no AE(s) following prior vaccinations.  No follow-up attempts are possible. No further information is expected.