Fentanyl transdermal patches are mainly used for analgesic purposes. The main component of these drugs is fentanyl. Fentanyl has a much stronger analgesic effect than morphine opioids. These drugs are made into patches that can be applied topically on the skin surface and have a slow, sustained release effect. These drugs are mainly used in clinical applications for moderate to severe pain caused by diseases, for example, in the following areas: 1. In the case of multiple injuries involving the whole body, these patches can be used as temporary pain relief because of the severe and continuous pain. 2, it can be applied to chronic pain caused by cancer. Some cancer patients may suffer from severe and continuous pain in multiple areas of the body due to metastasis of cancer. This patch can be used as a convenient analgesic treatment. 3. It is used for post-operative pain relief. If a patient has severe pain after surgery and there is no other good way to relieve pain, you can choose to use such patches topically as symptomatic treatment for analgesia.