Fentanyl

Question 1

Fentanyl Indications

Answer 1

Moderate to severe pain.
Cardiogenic pulmonary oedema with severe anxiety.
Rapid sequence intubation.
Sedation post intubation.
Symptom control during end of life care.

Question 2

Fentanyl Contraindications

Answer 2

Known severe allergy.
Unable to obey commands (exceptions: administration for RSI, end of life care
and post intubation).
Respiratory depression

Question 3

Fentanyl Cautions

Answer 3

Aged less than one year. Children under the age of one year are at increased
risk of respiratory depression following opiate administration.
At high risk of respiratory depression. For example, severe COPD, morbid
obesity or on home BiPAP. Such patients may develop respiratory depression
following opiate administration.
Labour. Opiates cross the placenta and may cause drowsiness and/or
respiratory depression in the baby, particularly when administered within
an hour or two of birth. Discuss administration with the lead maternity carer
if possible. Following birth, close observation of the baby is required and
personnel must be prepared to treat respiratory depression.
Concurrent administration of other opiates, ketamine or midazolam. This will
increase and prolong the effects.
Elderly and/or frail. These will increase and prolong the effects.
Signs of shock. Fentanyl may make shock worse.

Question 4

Fentanyl Common adverse effects

Answer 4

• Respiratory depression.
• Bradycardia.
• Hypotension.
• Sedation.
• Nausea and vomiting.
• Itch.
• Euphoria.

Question 5

Fentanyl Onset of Action

Answer 5

• IV: 2-5 minutes. The maximal analgesic and respiratory depressant effects may
not occur until 10-15 minutes and this may be longer in the elderly.
• IN: 5-10 minutes.
• IM: 5-10 minutes.

Question 6

Fentanyl Usual Duration of action

Answer 6

• 30-60 minutes.

* The effect on respiration may last for several hours.

Question 7

Fentanyl IV Analgesic Dose

Answer 7

a) 10-50 mcg every five minutes for an adult. Use a dose at the lower end of
the range if the patient is small, frail or cardiovascularly unstable.
Peadiatric dose - see paeds table

Question 8

Fentanyl IN for Analgesia

Answer 8

a) 100 mcg IN for an adult weighing 80 kg or less. Further doses of 50 mcg
may be administered every ten minutes without a maximum dose. Halve
these doses if the patient is frail or cardiovascularly unstable.
b) 200 mcg IN for an adult weighing greater than 80 kg. Further doses of
100 mcg may be administered every ten minutes without a maximum dose.
Halve these doses if the patient is frail or cardiovascularly unstable.
c) See the paediatric drug dose tables for a child.

Question 9

Fentanyl IM for analgesia if IV access cannot be obtained and IN administration is
inappropriate:

Answer 9

a) 50-100 mcg IM for an adult. Use a dose at the lower end of the range if the
patient is small, frail or cardiovascularly unstable. This may be repeated
once after 20 minutes.
b) See the paediatric drug dose tables for a child. This may be repeated once
after 20 minutes.

Question 10

Fentanyl Use in pregnancy

Answer 10

• Safety has not been demonstrated in pregnancy, but fentanyl should be
administered if indicated.
• May be administered if the patient is breastfeeding. Advise the patient to stop
breastfeeding and seek further advice from their lead maternity carer or GP.

Question 11

Fentanyl Pharmacokinetics

Answer 11

Fentanyl is more lipophilic (fat soluble) than morphine and this is why fentanyl
is well absorbed through the nasal mucosa.
• Fentanyl may cause a small amount of histamine release. In combination with
relief of pain this usually results in a small fall in blood pressure.
• Fentanyl is metabolised in the liver.
• There are no significant effects from liver impairment on acute administration.

Question 12

Fentanyl Common Interactions

Answer 12

• The effects will be increased in the presence of other opiates and sedatives, for
example benzodiazepines or alcohol.

Question 13

Fentanyl Transport advice/Additional Info

Answer 13

• A patient administered fentanyl must be given a clear recommendation to
be transported to a medical facility by ambulance, unless the patient is being
treated using the ‘end of life care’ section, the ‘patella dislocation’ section, or
the ‘shoulder dislocation’ section.
• Transport should usually be to an ED unless the patient has a chronic condition
and can be taken to a primary care facility with staff that know the patient well.

Question 14

Fentanyl Mechanism of action

Answer 14

Fentanyl is an opiate analgesic. It is an opiate agonist (or stimulator) that binds to opiate receptors in the brain and spinal cord causing analgesia.