Canterbury DHB


Fentanyl Information Sheet

See also: Management of Persistent Pain - Fentanyl

Sandoz™ transdermal patches, Fentanyl inj (AstraZeneca, DBL, Sublimaze™)

Fentanyl is a potent semi-synthetic opioid analgesic. It has similar pharmacology to morphine. It is indicated for use in the treatment of moderate to severe pain. Transdermal fentanyl is indicated for those with stable rather than acute pain. It is a useful alternative opioid especially for those patients with renal failure and in those who are experiencing severe adverse effects or, conversely, tolerance to their initial opioid (usually morphine). Unlike most other opioids, fentanyl patches cannot be used in opioid naïve patients due to concerns over the slow release nature of the patches. The injection can however be used in the opioid naïve. Sandoz™ patches are fully funded without Special Authority. Fentanyl is a controlled drug and is prescribed on a controlled drug prescription. Fentanyl injection is also fully funded.


Fentanyl acts as an agonist on mu opioid receptors and, like most opioids, on serotonin /noradrenaline pathways in the spinal cord. It is considered to be one of the more serotonergic opioids. Metabolites, e.g., norfentanyl are inactive.


fentanyl patch

fentanyl injection


Plasma half-life

17 hours (depot in skin)

3-4 hours

2-3 hours


CYP3A4 to inactive metabolites

CYP3A4 to inactive metabolites

glucuronidation to active metabolites


metabolised (only 10% excreted unchanged in urine)

metabolised (only 10% excreted unchanged in urine)

active metabolites mainly cleared renally

Interactions: CYP enzyme inhibitors e.g. fluconazole, fluoxetine, may increase efficacy and adverse effects while inducers e.g. carbamazepine, prednisone, may decrease efficacy. Fentanyl will also interact with other CNS depressants such as alcohol and benzodiazepines.


Fentanyl is available as transdermal patches (Sandoz™ 12.5, 25, 50, 75, 100 microgram/hour) and injection (AstraZeneca, DBL and Sublimaze™-100 microgram / 2 mL, 500 microgram / 10 mL).


Advantages of fentanyl

Disadvantages of fentanyl

Patient information

Sandoz Fentanyl Patch (PDF 143 KB)

More information and advice is available

For more information and advice within working hours, contact either the Christchurch Hospital Palliative Care Service on (03) 364 1473 or the Nurse Maude Hospice on (03) 375 4274. After hours, contact the Christchurch Hospital operator on (03) 364 0640 and ask for the palliative care clinician on call.

About this Canterbury DHB document (58012):

Document Owner:

Kate Grundy (see Who's Who)

Issue Date:

March 2016

Next Review:

March 2018


Note: Only the electronic version is controlled. Once printed, this is no longer a controlled document. Disclaimer

Topic Code: 58012