Compared with heroin, it is more potent, has higher profit margins, and, because it is compact, has simpler logistics. It can be cut into, or even replace entirely, the supply of heroin and other opiates. The flow of fentanyl mainly originates in Chinese factories which produce fentanyl or fentanyl precursors; it is then trafficked to other countries for illicit production and sale. In the United States, finished fentanyl arrives primarily from Mexico smuggled by cartels. Medical uses
Anesthesia
Intravenous fentanyl is often used for anesthesia and to treat pain. To induce anesthesia, it is given with a sedative-hypnotic, like propofol or thiopental, and a muscle relaxant. To maintain anesthesia, inhaled anesthetics and additional fentanyl may be used. These are often given in 15–30 minute intervals throughout procedures such as endoscopy and surgeries and in emergency rooms.For pain relief after surgery, use can decrease the amount of inhalational anesthetic needed for emergence from anesthesia. Balancing this medication and titrating the drug based on expected stimuli and the persons responses can result in stable blood pressure and heart rate throughout a procedure and a faster emergence from anesthesia with minimal pain. Regional anesthesia
Fentanyl is the most commonly used intrathecal opioid because its lipophilic profile allows a quick onset of action (5–10 min.) and intermediate duration of action (60–120 min.). Spinal administration of hyperbaric bupivacaine with fentanyl may be the optimal combination. The almost immediate onset of fentanyl reduces visceral discomfort and even nausea during the procedure.
In rare cases, it may be caused by a lack of active saposin A (a derivative of prosaposin).The buildup of unmetabolized lipids adversely affects the growth of the nerves protective myelin sheath (the covering that insulates many nerves) resulting in demyelination and severe progressive degeneration of motor skills. As part of a group of disorders known as leukodystrophies, Krabbe disease results from the imperfect growth and development of myelin.Galactosylceramidase deficiency also results in a buildup of a glycosphingolipid called psychosine, which is toxic to oligodendrocytes, a type of non-neuronal cell found in the nervous system, collectively termed neuroglia. Diagnosis
There are a few ways to help pinpoint the presence of Krabbe disease. Newborn screening for Krabbe disease includes assaying dried blood cells for GALC enzyme activity and molecular analysis for evidence of GALC enzyme mutations. Infants displaying low enzyme activity and/or enzyme mutations should be referred for additional diagnostic testing and neurological examination. 0-5% GALC enzyme activity is observed in all symptomatic individuals with Krabbe disease. High concentration of psychosine in dried blood spots may also be identified as a marker for Krabbe disease. A 2011 study discovered that individuals with Krabbe disease, more so in later-onset individuals, tend to have an abnormal increase in CSF protein concentration.The disease may be diagnosed by its characteristic grouping of certain cells (multinucleated globoid cells), nerve demyelination and degeneration, and destruction of brain cells. Special stains for myelin (e.g., luxol fast blue) may be used to aid diagnosis. New York, Missouri and Kentucky include Krabbe in the newborn screening panel.