Adverse events (also called adverse effects or side effects) refer to unintended and harmful effects of a medication, treatment, or intervention that occur in addition to the desired therapeutic effects. These effects can range from mild and temporary to severe and long-lasting. They can also have a minimal and limited effect on the person experiencing an adverse effect through to a long term and severe effect. In very severe cases, adverse side effects may lead to death. Adverse effects are important to monitor because they can impact a patient’s health and quality of life.
Examples of adverse side effects in transfusion include fainting (blood donation), fever, chills or haemolytic transfusion reactions following receipt of a blood transfusion.
Side effect