DURAGESIC® (fentanyl transdermal system) is a transdermal
system providing continuous systemic
delivery of fentanyl,
a potent opioid analgesic,
for 72 hours. The chemical
name is N-Phenyl-N-(1-2-phenylethyl-4-piperidyl) propanamide.
The molecular weight
of fentanyl base is 336.5,
and the empirical
formula is C22H28N2O. The n-octanol:water
partition coefficient is 860:1. The pKa is 8.4.
System Components and Structure
The amount of fentanyl released from each system
per hour is proportional
to the surface area
(25 µg/h per 10 cm2).
The composition per unit
area of all system
sizes is identical. Each system
also contains 0.1 mL of alcohol
USP per 10 cm2.
* Nominal delivery
** FOR USE ONLY
IN OPIOID TOLERANT PATIENTS
DURAGESIC® is a rectangular transparent
unit comprising a protective
liner and four functional
layers. Proceeding from the outer surface toward the surface
adhering to skin, these
1) a backing layer of
polyester film; 2) a drug
reservoir of fentanyl
and alcohol USP gelled
with hydroxyethyl cellulose;
3) an ethylene-vinyl acetate
that controls the rate of fentanyl delivery
to the skin surface; and
4) a fentanyl containing silicone
adhesive. Before use, a protective
liner covering the adhesive
layer is removed and discarded.
The active component
of the system is fentanyl.
The remaining components are pharmacologically inactive. Less than
0.2 mL of alcohol is
also released from the system
Do not cut or damage DURAGESIC®.
If the DURAGESIC® system is cut
or damaged, controlled drug
not be possible.