Fentanyl can be administered intravenously, intramuscularly, and as a fentanyl transdermal patch. Fentanyl is mainly used as an anesthetic adjuvant and intravenous combined anesthesia, and can also be administered through the epidural or subarachnoid space for the treatment of acute post-surgical pain and chronic pain. Fentanyl transdermal patch can maintain blood concentration for 72 hours, stable analgesic effect, suitable for patients with moderate to severe cancer pain. Fentanyl in intravenous and intramuscular injection should pay attention to the dose, speed, to avoid respiratory depression, impaired consciousness and other adverse reactions, repeated use of the drug can produce dependence. In addition bronchial asthma, myasthenia gravis, craniocerebral tumors or trauma-induced coma patients are prohibited, and fentanyl is also prohibited for children under 2 years of age. Fentanyl is a nationally controlled drug, and can only be used by a doctor with a special prescription based on the condition of the patient, and should be used in strict accordance with medical advice, and should not be abused.