Adverse Event Reporting is a process used to document any negative effects or unexpected problems that occur after a medical treatment, medication, or vaccine is administered. This reporting helps healthcare professionals and regulatory agencies, like the FDA, monitor the safety and effectiveness of products, ensuring that any potential risks are identified and addressed. When an adverse event is reported, it is analyzed to determine if there is a connection to the treatment. This information is crucial for improving patient safety and can lead to changes in how a product is used or even its withdrawal from the market if necessary.