Particular compounds existing in grapefruit are acknowledged to inhibit CYP450 3A4 and may raise the bioavailability of swallowed fentanyl (reportedly as much as 75% of the dose) and Grownup:Patches deliver fentanyl in doses that range from: 12-100 mcg/hr. Doses needs to be independently titrated determined by past usage of opioids. Opioid-naive