Fentanyl is a synthetic opioid analgesic used to treat severe pain, especially in cancer patients, or for pain management during surgery. It is one of the most powerful opioids, with potencies about 50 to 100 times more potent than morphine. Because of its potency, fentanyl is generally used for severe pain that cannot be managed … What kind of drug is fentanyl? Learn about fentanyl. 계속 읽기