Phentanyl PK/PD, a valid drug.

With the advent of the new opioids in the anesthetic drug market, we may think that we have molecules available to replace the legendary fentanyl. However, studying its pharmacodynamic and pharmacokinetic properties, fentanyl can still be appropriately used to take advantage of its excellent analgesia and safety, comparable to that of other opioids when administered in accordance with pharmacokinetic models. We must not forget however that several drugs frequently used during anesthesia (midazolam, dexametasone, prednisolone, ketamin, etc.), may impact the metabolism of fentanyl on account of the cytochrome P450 3A4 enzyme. The knowledge and judicious application of pharmacokinetic models serve to estimate plasma concentrations in order to ensure the best analgesic conditions associated to synergies with the frequent use of hypnotics such as propofol and desfluorane. Fentanyl is best used for specific indications such as extended surgical procedures (over 120 minutes) or procedures that stimulate the patient's pain perception. [ABSTRACT FROM AUTHOR]