These results were quite similar to those from our previous study.

AZD122 resulted in more adverse reactions after vaccination than BNT162b2. Among the mild cases, the proportion of women was high, and the proportion of men was high among the severe cases. Digestive symptoms mainly occurred following administration of the first vaccine dose, with symptom onset usually occurring within one day. In this study, the most common digestive symptoms were abdominal pain and diarrhea, whereas the most common complication was enterocolitis. However, compared to patients with COVID-19, , ], vaccinated individuals had a faster onset of symptoms, a higher rate of asymptomatic infections, and lower severity and mortality. These have been described as “Vaccine-Induced COVID-19 Mimicry” Syndrome, a condition caused by COVID-19 vaccines. Additionally, there are reports of various complications, including acute liver disease, acute acalculous cholecystitis, acute pancreatitis, intestinal obstruction, acute colon pseudoobstruction, and mesenteric ischemia, ,, , ].Īdverse reactions following COVID-19 vaccination are rather similar to complications in COVID-19 patients. Patients with COVID-19 frequently experience digestive symptoms such as abdominal pain, vomiting, anorexia, diarrhea, and nausea. SARS-CoV-2 causes digestive complications and can invade several digestive organs by binding to angiotensin-converting enzyme-2 receptors, abundant in several gastrointestinal organs. The exclusion criteria were as follows: (1) gastrointestinal symptoms prior to vaccination (2) no history of recent COVID-19 infection (3) positive real-time polymerase chain reaction test results for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and (4) no history of medications that can cause indigestion. The inclusion criteria were as follows: (1) newly developed gastrointestinal symptoms after vaccination (symptom onset is measured after vaccination) and no gastrointestinal symptoms prior to vaccination (2) gastrointestinal symptoms requiring medical treatment (3) gastrointestinal symptoms result in a major portion of the patient's discomfort (4) patients visiting the ED for gastrointestinal symptoms. Only those that had an association between vaccination and digestive symptoms were included in the study. We collected cases of patients who visited the ED for digestive symptoms following COVID-19 vaccination.

The requirement for informed consent was waived because of the retrospective nature of the study. The study protocol was approved by the Institutional Review Board of the Seoul National University Boramae Medical Center (approval number 30–2021-113). This retrospective single-center study was conducted at the Seoul National University Boramae Medical Center in Seoul, South Korea, from March 1 to July 30, 2021. Therefore, we aimed to investigate the clinical characteristics and outcomes of patients experiencing digestive symptoms following COVID-19 vaccination. There is insufficient information regarding the clinical characteristics of digestive symptoms following the vaccination. However, some critical complications were identified in patients with digestive symptoms in the emergency department (ED). Previous studies reported that digestive symptoms following COVID-19 vaccination were not severe AEs, and they could be managed without medical treatment. The common side effects include headache, muscle pain, chills, diarrhea, and pain at the inoculation site. Most AEs following COVID-19 vaccination are mild and transient. However, rare and critical complications such as encephalomyelitis, anaphylaxis, vesiculo-bullous rash, acute kidney injury, intravascular thrombosis, and thrombocytopenia, , ] have been reported following vaccine administration. These vaccines are effective in preventing COVID-19 infection and are generally safe to use with a low incidence of adverse events (AEs), ,, ,, , 10]. Four COVID-19 vaccines have been approved for use in South Korea: AZD1222 (AstraZeneca), BNT162b2 (Pfizer–BioNTech), JNJ-78436735 (Janssen), and mRNA-1273 (Moderna) they are currently in use as of August 20, 2021.

COVID-19 vaccines are the primary defense against the pandemic they reduce disease severity and mortality. The World Health Organization declared the coronavirus disease (COVID-19) outbreak a global pandemic in March 2020.

Pfizer vaccine side effect throwing up