Hi there! Well, it depends on which type of Fentanyl you are using: Fentanyl transdermal, injectable, or the transmucosal.
[the patches release anywhere from 25 mcq, 50 mcq, 75 mcq, or 100 mcq of Fentanyl per hour. each patch is changed or applied every 72 hours, but you probably know that]
I would hope that, before any type of pain medication is ordered or offered, the health care provider would assess the inferred pathophysiology or the mechanisms that may be responsible for the pain the person if experiencing (nociceptive pain, neuropathic pain, or idiopathic pain)
What type of pain medication has your patient received in the past, and how effective was it/wasn't it?
to manage chronic pain alot of pain management providers would start therapy with the 25 mcq/hour transdermal system and adjust the dosage prn and as tolerated. Onset of action is 12-24 hours and peaks within 1-3 days, duration varies.
May I ask, what type of pain medication has your patient been receiving? Oftentimes many health care providers under medicate their patients because they don't want the patient to become "addicted or dependent". As many may know, there are two types of dependency: physiological and psychological. The former means the body becomes more tolerant of the dosage and over time, increase in the dose or adding a different type of pain medication is needed.
There is an excellent website maintained by Beth Israel Medical Center's Pain and Palliative Care Unit, NYC. Maybe if you get the chance check it out. www.stoppain.org