Fentanyl

Registered South African indications:

• Anaesthesia
• Analgesia
• Anaesthetic premedication

Contraindications

• Hypersensitivity to the active ingredient or any of its excipients
• Respiratory depression
• Obstructive airways disease
• Coadministration with monoamine oxidase inhibitors or within 14 days of their use 

Cautions

• Pregnancy
• Breastfeeding
• Moderate to severe renal impairment (eGFR <50ml/min/1.73m²)
• Hepatic impairment
• Elderly
• Tolerance and dependence may occur
• High doses
• Infusions 
• Administration in labour 
• Compromised intracerebral compliance
• Uncontrolled hypothyroidism
• Pulmonary disease or decreased respiratory reserve
• Alcoholism 
• Chronic opioid therapy
• History of opioid abuse
• Myasthenia gravis
• Controlled sodium diet
• Children
• May impair ability to drive and operate machinery

Forms avail. in SA and covered in this monograph: inj

Analgesic supplement to general anaesthesia 
- Minor, painful surgery

• IV: 2μg/kg

Analgesic supplement to general anaesthesia 
- Complicated surgery

• IV: 2-20μg/kg

Analgesic supplement to general anaesthesia 
- Major surgery

• IV: 20-50μg/kg; Titrate by 25-250μg as needed; Treatment duration: Until surgical completion

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When given with nitrous oxide/oxygen it has an attenuating effect

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When dosages in this range are used during surgery, post-operative ventilation and observation are essential in view of the possibility of extended post-operative respiratory depression

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Post-operative analgesia

• IM: 0.07-1.4μg/kg; May be repeated in 1-2hrs as needed

Anaesthesia with spontaneous respiration

• IV: Initial: 50-200μg,; Titrate by 50μg as needed

Anaesthesia with assisted respiration

• IV: Initial: 300-3500μg; Titrate by 100-200μg as needed

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Admin. together with oxygen and muscle relaxant

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Adjunct to local anaesthetic

• IV: 0.07 - 1.4 μg/kg

Premedication

• IM: 0.07 - 1.4 μg/kg, 30-60 minutes prior to surgery

Combined with neuroleptic

• IV: Supplement with 1μg/kg, at 20min intervals

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Secondary respiratory depression after the operation has been observed

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An opioid antagonist, resuscitative equipment and oxygen should be readily available

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Doses in excess of 200μg are for use in anaesthesia only

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Unless planning to ventilate post operatively, infusion should be stopped 40min before end of surgery

Paed. forms avail. in SA and covered in this monograph: inj

Paed. dosages below include:

• South African Standard Treatment Guidelines indications and dosages
• Indications and dosages registered in other jurisdictions

South African Standard Treatment Guidelines indications and dosages

• Click here for the Pain Control (Standard Treatment Guidelines And Essential Medicines List For South Africa, Hospital Level, Paediatrics, 2023 Edition)
• Click here for the Anaesthetics (Standard Treatment Guidelines And Essential Medicines List For South Africa, Hospital Level, Paediatrics, 2023 Edition)

Indications and dosages registered in other jurisdictions

Induction and maintenance of anaesthesia 

Younger than 2 years

• Not established for use

Between 2-11 years

• IV: Initial: 1-3μg/kg; Titrate by 1-1.25μg/kg as needed

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For specific indications, doses up to 10-15μg/kg can be used with mechanical ventilation

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Older than 11 years

• See adult dosage

Pregnancy

• Caution
• There are no adequate data from the use of fentanyl in pregnant women. Fentanyl can cross the placenta in early pregnancy. Studies in animals have shown some reproductive toxicity. The potential risk for humans is unknown
• Administration during childbirth (including caesarean section) is not recommended because fentanyl crosses the placenta and may suppress spontaneous respiration in the newborn period. If fentanyl is administered, assisted ventilation equipment must be immediately available for the mother and infant if required. An opioid antagonist for the child must always be available

Breastfeeding

• Caution; not recommended
• Fentanyl is excreted into human milk. Therefore breastfeeding is not recommended within 24 hours of treatment. The risk/ benefit of breastfeeding following fentanyl administration should be considered

Renal Impairment

• eGFR ≥50ml/min/1.73m²: No dose adjustment recommended
• eGFR <50ml/min/1.73m²: Caution; no dose adjustment recommended
  Reserve fentanyl for use in patients with renal impairment for whom alternative treatment options are ineffective, not tolerated, or would be otherwise inadequate to provide sufficient management of pain

eGFR (ml/min/1.73m2)	Dose
≥50	No adjustment necessary
11-49	Administer 75% of recommended dose
<10  on Intermittent/Peritoneal dialysis	Administer 50% of recommended dose
Continuous Renal Replacement Therapy (CRRT)	Administer 75% of recommended dose

Hepatic Impairment

• Caution; no dose adjustment recommended

Elderly

• Caution; no dose adjustment recommended
  The elderly, as compared to adults, are more susceptible to adverse effects including CNS depressant and constipating effects of opioids; therefore, use with caution
  Initiate therapy with the lowest dose possible for the clinical situation
  Alternative routes of administration like transdermal patches for chronic pain management use are preferable

Porphyria Information

• Probably not porphyrinogenic (PNP)

Drugs in Sport

• Prohibited - In competition

Central Nervous System Disorders

• Dyskinesia
• Sedation
• Dizziness
• Headache
• Seizures 
• Loss of consciousness
• Myclonus
• Agitation
• Euphoric mood
• Postoperative confusion
• Restlessness
• Postoperative hallucinatory episodes
• Extrapyramidal symptoms

Cardiovascular Disorders

• Hypotension
• Hypertension
• Venous pain
• Phlebitis
• Blood pressure fluctauation
• Bradycardia
• Tachycardia
• Arrhythmia
• Cardiac arrest 

Respiratory Disorders

• Laryngospasm
• Bronchospasm
• Apnoea
• Hyperventilation
• Hiccups
• Respiratory depression airway complication of anaesthesia 

Gastrointestinal Disorders

• Nausea and vomiting

Endocrine and Metabolic Disorders

• Chills
• Hypothermia

Musculoskeletal Disorders

• Muscle rigidity

Skin and Subcutaneous Tissue Disorders

• Allergic dermatitis
• Pruritus 

Immune, Blood and Lymphatic System Disorders

• Hypersensivity

Sensory Disorders

• Visual disorders 

• Opioid premedication
• Barbiturates
• Benzodiazepines
• Neuroleptics
• Halogenic gases 
• Ritonavir
• Fluconazole 
• Voriconazole 
• CYP3A4 inhibitors
• Non-vagolytic muscle relaxants
• Selective serotonin reuptake inhibitors
• Serotonin norepinephrine reuptake inhibitors
• Monoamine oxidase inhibitors
• Etomidate

• Vital signs
• Respiratory status
• Cardiovascular status

Fentanyl is an opioid analgesic that interacts predominately with the opioid mu-receptor but also binds to kappa and delta-type opioid receptors. These mu-binding sites are discretely distributed in the human brain, spinal cord, and other tissues. Its primary actions of therapeutic value are analgesia and sedation. Fentanyl may increase the patient's tolerance for pain and decrease the perception of suffering, although the presence of the pain itself may still be recognized.

Injection (per ml) 50μg

• Sublimaze (Piramal Critical) originator

Injection (per 2ml) 100μg

• Fentanyl-Fresenius (Fresenius)
• Pharma-Q Fentanyl (Pharma-Q)

Injection (per 10ml) 500μg

• Fentanyl-Fresenius (Fresenius)
• Pharma-Q Fentanyl (Pharma-Q)