Which of the following is not a method of administering fentanyl?

Fentanyl is a potent opioid used primarily for pain management, and it can be administered through several routes, including intravenous (IV), intramuscular (IM), and intraosseous (IO) methods. These routes allow for rapid absorption into the bloodstream and are often used in medical settings for the immediate management of pain, especially in emergencies.

However, the administration of fentanyl via nebulization is not a recognized or practical method for delivering the drug. While nebulization is a common route for certain medications, particularly those targeting the respiratory system, fentanyl is not typically administered this way due to its classification and the specific physiological effects it has when delivered into the systemic circulation. Instead, fentanyl is usually provided through the aforementioned routes, which are much more effective for achieving the desired analgesic effects. Thus, the option indicating nebulization is the least appropriate method for administering fentanyl.