Data fra intravenøse studier med fentanyl tyder på, at ældre patienter kan have nedsat clearance og forlænget halveringstid, og de kan være mere følsomme over for det aktive stof end yngre patienter.
Data from intravenous studies with fentanyl suggest that elderly patients may have reduced clearance, a prolonged half-life and they may be more sensitive to the active substance than younger patients.