This guide explains Patient Controlled Analgesia (PCA), a computerized pain relief system that allows patients to self-administer prescribed painkillers like morphine or fentanyl after surgery. It covers how the system works, safety features, benefits including better pain control and faster recovery, potential side effects, monitoring procedures, and duration of use. The resource addresses common concerns about addiction and provides information about alternative pain management options for patients who choose not to use PCA.