Fentanyl, also spelled fentanil, is an opioid which is used as a pain medication & together with other medications for anesthesia. It has a rapid onset & effects generally last less than an hour. Fent... View MoreFentanyl, also spelled fentanil, is an opioid which is used as a pain medication & together with other medications for anesthesia. It has a rapid onset & effects generally last less than an hour. Fentanyl is available in a number of forms including by injection, as a skin patch, & to be absorbed through the tissues inside the mouth. You can also rarely found Fentanyl in Powder form. The Powder is commonly used in Laboratories.789 Mission St, San Francisco, CA 94103 UsaWebsite: buyfentanly.us/product/buy-fentanyl-powder-25g-pack/