Fentanyl Transdermal System
Fentanyl Transdermal System (Duragesic)
Fentanyl Transdermal System
( FEN-tah-nil)
Pregnancy Category: C Duragesic-25, -50, -75, and -100 (C-II) (Rx)

Classification: Narcotic analgesic, morphine type

See Also: See also Narcotic Analgesics and Fentanyl citrate .

Action/Kinetics: The system provides continuous delivery of fentanyl for up to 72 hr. The amount of fentanyl released from each system each hour depends on the surface area (25 mcg/hr is released from each 10 cm ²). Each system also contains 0.1 mL of alcohol/10 cm ²; the alcohol enhances the rate of drug flux through the copolymer membrane and also increases the permeability of the skin to fentanyl. Following application of the system, the skin under the system absorbs fentanyl, resulting in a depot of the drug in the upper skin layers, which is then available to the general circulation. After the system is removed, the residual drug in the skin continues to be absorbed so that serum levels fall 50% in about 17 hr. Metabolized in the liver and excreted mainly in the urine.

Uses: Restrict use for the management of severe chronic pain that cannot be managed with less powerful drugs. Only use 50, 75, and 100 mcg/hr doses on clients already on and tolerant to narcotic analgesics and who require continuous narcotic administration.

Contraindications: Use for acute or postoperative pain (including out-patient surgeries). To manage mild or intermittent pain that can be managed by acetaminophen-opioid combinations, NSAIDs, or short-acting opioids. Hypersensitivity to fentanyl or adhesives. ICP, impaired consciousness, coma, medical conditions causing hypoventilation. Use during labor and delivery. Use of initial doses exceeding 25 mcg/hr, use in children less than 12 years of age and clients under 18 years of age who weigh less than 50 kg. Lactation.

Special Concerns: Use with caution in clients with brain tumors and bradyarrhythmias, as well as in elderly, cachectic, or debilitated individuals. Use Duragesic-50, -75, and -100 only in opioid-tolerant clients. Safety and efficacy have not been determined in children.

Additional Side Effects: Sustained hypoventilation.

How Supplied: Film, Extended Release: 25 mcg/hr, 50 mcg/hr, 75 mcg/hr, 100 mcg/hr

Dosage
?Transdermal System Analgesia.
Adults, usual initial: 25 mcg/hr unless the client is tolerant to opioids (Duragesic-50, -75, and -100 are intended for use only in clients tolerant to opioids). Initial dose should be based on (1) the daily dose, potency, and characteristics (i.e., pure agonist, mixed agonist/antagonist) of the drug the client has been taking; (2) the reliability of the relative potency estimates used to calculate the dose as estimates vary depending on the route of administration; (3) the degree, if any, of tolerance to narcotics; and (4) the general condition and status of the client.
To convert clients from PO or parenteral opioids to the transdermal system, the following method should be used: (1) the previous 24-hr analgesic requirement should be calculated; (2) convert this amount to the equianalgesic PO morphine dose; (3) find the calculated 24-hr morphine dose and the corresponding transdermal fentanyl dose using the table provided with the product; and (4) initiate treatment using the recommended fentanyl dose. The dose may be increased no more frequently than 3 days after the initial dose or q 6 days thereafter. The ratio of 90 mg/24 hr of PO morphine to 25 mcg/hr increase in transdermal fentanyl dose should be used to base appropriate dosage increments on the daily dose of supplementary opioids.