Abstract
COVID-19 has been spreading worldwide. Therefore, the COVID-19 vaccine is recommended for prevention. However, adverse events after COVID-19 vaccination remain an issue, and we should monitor patients for adverse events and determine their association with COVID-19 vaccination. Here, we report a case involving a 48-year-old Japanese woman who experienced dull left leg pain that resolved spontaneously after the first vaccine dose, followed by deep vein thrombosis (DVT) and pulmonary embolism (PE) after the second dose. The findings from this case suggest that the COVID-19 vaccine could cause severe adverse events, such as DVT. Therefore, patients should understand their subjective symptoms and report any side effects experienced after the first dose before they take the second dose. Furthermore, medical providers should enquire about all possible symptoms experienced after the initial dose before they administer the second dose.