Fentanyl patches are medical devices used to deliver a strong pain medication called fentanyl through the skin. They are typically prescribed for patients with severe pain, such as those recovering from surgery or dealing with chronic pain conditions. The patches release a controlled amount of medication over time, usually lasting up to three days. These patches are designed for individuals who have already developed a tolerance to other pain medications. It is important to use them exactly as prescribed, as misuse can lead to serious side effects, including respiratory depression and overdose.