Fentanyl solution for injections 0.005%

Overdose

Symptoms and signs:

The manifestations of Fentanyl solution for injections 0.005% overdosage are generally an extension of its pharmacological action. Depending on the individual sensitivity, the clinical picture is determined by the degree of respiratory depression, which varies from bradypnoea to apnoea.

Treatment:

The patient should be carefully observed; body warmth and adequate fluid intake should be maintained. If hypotension is severe or if it persists, the possibility of hypovolaemia should be considered and, if present, it should be controlled with appropriate parenteral fluid administration.

Contraindications

Incompatibilities

The product is chemically incompatible with the induction agents thiopentone and methohexitone because of the wide differences in pH.

Pharmaceutical form

Undesirable effects

The safety of Fentanyl solution for injections 0.005% IV was evaluated in 376 subjects who participated in 20 clinical trials evaluating Fentanyl solution for injections 0.005% IV as an anaesthetic. These subjects took at least 1 dose of Fentanyl solution for injections 0.005% IV and provided safety data. Based on pooled safety data from these clinical trials, the most commonly reported (> 5% incidence) Adverse Drug Reactions (ADRs) were (with % incidence): nausea (26.1); vomiting (18.6); muscle rigidity (10.4); hypotension (8.8); hypertension (8.8); bradycardia (6.1) and sedation (5.3).

Including the above-mentioned ADRs, Table 1 displays ADRs that have been reported with the use of Fentanyl solution for injections 0.005% IV from either clinical trials or postmarketing experience.

The displayed frequency categories use the following convention: Very common (>1/10); common (>1/100 to <1/10); uncommon (>1/1,000 to <1/100); rare (>1/10,000 to <1,1000); very rare (<10,000); and not known (cannot be estimated from the available clinical trial data).

Table 1: Adverse Drug Reactions

When a neuroleptic is used with Fentanyl solution for injections 0.005% the following adverse reactions may be observed: chills and/or shivering, restlessness, postoperative hallucinatory episodes and extrapyramidal symptoms.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard

Preclinical safety data

In vitro Fentanyl solution for injections 0.005% showed, like other opioid analgesics, mutagenic effects in a mammalian cell culture assay, only at cytotoxic concentrations and along with metabolic activation. Fentanyl solution for injections 0.005% showed no evidence of mutagenicity when tested in in vivo rodent studies and bacterial assays. In a two-year rat bioassay, Fentanyl solution for injections 0.005% was not carcinogenic.

Some tests on female rats showed reduced fertility as well as embryo mortality. These findings were related to maternal toxicity and not a direct effect of the drug on the developing embryo. There was no evidence of teratogenic effects.

Therapeutic indications

Fentanyl solution for injections 0.005% citrate is an opioid analgesic used:

In low doses to provide analgesia during short surgical procedures.

In high doses as an analgesic/respiratory depressant in patients requiring assisted ventilation.

In combination with a neuroleptic in the technique of neuroleptanalgesia.

In the treatment of severe pain, such as the pain of myocardial infarction.

Pharmacotherapeutic group

Pharmacodynamic properties

Pharmacotherapeutic group: Anaesthetic general, opioid anaesthetic.

ATC code: N01AH01

Fentanyl solution for injections 0.005% is a synthetic opiate with a clinical potency of 50 to 100 times that of morphine. Its onset of action is rapid and its duration of action is short. In man, a single IV dose of 0.5-1 mg/70 kg body weight immediately produces a pronounced state of surgical anaesthesia, respiratory depression, bradycardia and other typical morphine-like effects. The duration of action of the peak effects about 30 minutes. All potent morphine-like drugs produce relief from pain, ventilatory depression, emesis, constipation, physical dependence, certain vagal effects and varying degrees of sedation. Fentanyl solution for injections 0.005%, however, differs from morphine not only by its short duration of action but also by its lack of emetic effect and minimal hypotensive activity in animals.

Pharmacokinetic properties

Some pharmacokinetic parameters for Fentanyl solution for injections 0.005% are as follows:

Urinary excretion = 8%

Bound in plasma = 80%

Clearance (ml/min/kg) = 13±2

Volume of distribution (litres/kg) = 4.0±0.4

Estimates of terminal half-life range from 141 to 853 minutes.

Renal impairment

Data obtained from a study administering IV Fentanyl solution for injections 0.005% in patients undergoing renal transplantation suggest that the clearance of Fentanyl solution for injections 0.005% may be reduced in this patient population.).

Obese Patients

An increase in clearance of Fentanyl solution for injections 0.005% is observed with increased body weight. In patients with a BMI >30, clearance of Fentanyl solution for injections 0.005% increases by approximately 10% per 10 kg increase of the fat free mass (lean body mass).

Name of the medicinal product

Qualitative and quantitative composition

Special warnings and precautions for use

Warnings:

Tolerance and dependence may occur. Following intravenous administration of Fentanyl solution for injections 0.005%, a transient fall in blood pressure may occur, especially in hypovolaemic patients. Appropriate measures to maintain a stable arterial pressure should be taken.

Respiratory Depression

As with all potent opioids, profound analgesia is accompanied by marked respiratory depression, which may persist into or recur in the early postoperative period. Care should be taken after large doses or infusions of Fentanyl solution for injections 0.005% to ensure that adequate spontaneous breathing has been established and maintained before discharging the patient from the recovery area.

Significant respiratory depression will occur following the administration of Fentanyl solution for injections 0.005% in doses in excess of 200 mcg. This, and the other pharmacological effects of Fentanyl solution for injections 0.005%, can be reversed by specific narcotic antagonists (e.g. naloxone). Additional doses of the latter may be necessary because the respiratory depression may last longer than the duration of action of the opioid antagonist.

Resuscitation equipment and opioid antagonists should be readily available. Hyperventilation during anaesthesia may alter the patients response to CO2, thus affecting respiration postoperatively.

Administration in labour may cause respiratory depression in the new-born infant.

Cardiac disease

Bradycardia and possibly asystole can occur if the patient has received an insufficient amount of anticholinergic, or when Fentanyl solution for injections 0.005% is combined with non-vagolytic muscle relaxant. Bradycardia can be antagonised by atropine.

Muscle rigidity

Muscular rigidity (morphine-like effect) may occur.

Rigidity, which may also involve the thoracic muscles, can be avoided by the following measures:

- slow I.V. injection (usually sufficient for lower doses)

- premedication with benzodiazepines

- use of muscle relaxants.

Non-epileptic (myo)clonic movement can occur

Special dosing conditions

The use of rapid bolus injections of opioids should be avoided in patients with compromised intracerebral compliance; in such patients the transient decrease in the mean arterial pressure has occasionally been accompanied by a transient reduction of the cerebral perfusion pressure.

It is wise to reduce dosage in the elderly and debilitated patients.

In uncontrolled hypothyroidism, pulmonary disease, decreased respiratory reserve, alcoholism and liver or renal impairment the dosage should be titrated with care and prolonged post-operative monitoring may be required.

Patients on chronic opioid therapy or with a history of opioid abuse may require higher doses.

Myasthenia gravis

In patients with myasthenia gravis, careful consideration should be applied in the use of certain anticholinergic agents and neuromuscular-blocking pharmaceutical agents prior to, and during, the administration of a general anaesthetic regimen which includes administering intravenous Fentanyl solution for injections 0.005%.

Precautions:

Fentanyl solution for injections 0.005% should be given only in an environment where the airway can be controlled and by personnel who can control the airway.

Interaction with neuroleptics:

If Fentanyl solution for injections 0.005% is administered with a neuroleptic, the user should be familiar with the special properties of each drug, particularly the difference in duration of action. When such a combination is used, there is a higher incidence of hypotension. Neuroleptics can induce extrapyramidal symptoms that can be controlled with anti-Parkinson agents.

Bile duct:

As with other opioids, due to the anticholinergic effects, administration of Fentanyl solution for injections 0.005% may lead to increases of bile duct pressure and, in isolated cases, spasms of the Sphincter of Oddi might be observed.

Serotonin Syndrome:

Caution is advised when Fentanyl solution for injections 0.005% is co-administered with drugs that affect the serotonergic neurotransmitter systems.

The development of a potentially life-threatening serotonin syndrome may occur with the concomitant use of serotonergic drugs such as Selective Serotonin Re-uptake Inhibitors (SSRIs) and Serotonin Norepinephrine Re-uptake Inhibitors (SNRIs), and with drugs which impair metabolism of serotonin (including Monoamine Oxidase Inhibitors [MAOIs]). This may occur within the recommended dose.

Serotonin syndrome may include mental-status changes (e.g., agitation, hallucinations, coma), autonomic instability (e.g., tachycardia, labile blood pressure, hyperthermia), neuromuscular abnormalities (e.g., hyperoreflexia, incoordination, rigidity), and/or gastrointestinal symptoms (e.g., nausea, vomiting, diarrhoea).

If serotonin syndrome is suspected, rapid discontinuation of Fentanyl solution for injections 0.005% should be considered.

Paediatric population

Techniques that involve analgesia in a spontaneous breathing child should only be used as part of an anaesthetic technique, or given as part of a sedation/analgesia technique with experienced personnel in an environment that can manage sudden chest wall rigidity requiring intubation, or apnoea requiring airway support.

Fentanyl solution for injections 0.005% Injection contains 3.5 mg sodium per ml of solution, equivalent to 0.18% of the WHO recommended maximum daily intake of 2 g sodium for an adult. To be taken into consideration by patients on a controlled sodium diet.

Effects on ability to drive and use machines

Where early discharge is envisaged, patients should be advised not to drive or to operate machinery for 24 hours following administration.

This medicine can impair cognitive function and can affect a patient's ability to drive safely. This class of medicine is in the list of drugs included in regulations under 5a of the Road Traffic Act 1988. When prescribing this medicine, patients should be told:

- The medicine is likely to affect your ability to drive

- Do not drive until you know how the medicine affects you

- It is an offence to drive while under the influence of this medicine

- However, you would not be committing an offence (called 'statutory defence') if:

o The medicine has been prescribed to treat a medical or dental problem and

o You have taken it according to the instructions given by the prescriber and in the information provided with the medicine and

o It was not affecting your ability to drive safely

Dosage (Posology) and method of administration

Routes of administration

Fentanyl solution for injections 0.005% should be given only in an environment where the airway can be controlled and by personnel who can control the airway

Intravenous administration, either as a bolus or by infusion.

Intramuscular administration.

To avoid bradycardia, it is recommended to administer a small intravenous dose of an anti-cholinergic just before anaesthetic induction.

Posology

Fentanyl solution for injections 0.005% Injection 50 micrograms/ml, by the intravenous route, can be administered to both adults and children. The dose of Fentanyl solution for injections 0.005% Injection 50 micrograms/ml should be individualised according to age, body weight, physical status, underlying pathological condition, use of other drugs and type of surgery and anaesthesia.

Adults

The usual dosage regime is as follows:

Doses in excess of 200 micrograms are for use in anaesthesia only.

As a premedicant, 1-2 ml Fentanyl solution for injections 0.005% Injection 50 micrograms/ml may be administered intramuscularly 45 minutes before induction of anaesthesia.

After intravenous administration in unpremedicated adult patients, 2 ml of Fentanyl solution for injections 0.005% Injection 50 micrograms/ml may be expected to provide sufficient analgesia for 10 - 20 minutes in surgical procedures involving low pain intensity. 10 ml Fentanyl solution for injections 0.005% Injection 50 micrograms/ml injected as a bolus gives analgesia lasting about one hour. The analgesia produced is sufficient for surgery involving moderately painful procedures. Giving a dose of 50mcg/kg Fentanyl solution for injections 0.005% Injection 50 micrograms/ml will provide intense analgesia for some four to six hours for intensely stimulating surgery.

Fentanyl solution for injections 0.005% Injection 50 micrograms/ml may also be given as an infusion. In ventilated patients, a loading dose of Fentanyl solution for injections 0.005% Injection 50 micrograms/ml may be given as a fast infusion of approximately 1 mcg/kg/min for the first 10 minutes followed by an infusion of approximately 0.1 mcg/kg/min. Alternatively the loading dose of Fentanyl solution for injections 0.005% Injection 50 micrograms/ml may be given as a bolus. Infusion rates should be titrated to individual patient response; lower infusion rates may be adequate. Unless it is planned to ventilate post-operatively, the infusion should be terminated at about 40 minutes before the end of surgery.

Lower infusion rates, e.g. 0.05-0.08 mcg/kg/minute are necessary if spontaneous ventilation is to be maintained. Higher infusion rates (up to 3 mcg/kg/minute) have been used in cardiac surgery.

Fentanyl solution for injections 0.005% Injection is chemically incompatible with the induction agents thiopentone and methohexitone because of wide differences in pH.

Use in elderly and debilitated patients: It is wise to reduce the dosage in the elderly and debilitated patients. The effect of initial dose should be taken into account in determining supplemental doses.

Paediatric population

Children aged 12 to 17 years old: Follow adult dosage.

Children aged 2 to 11 years old:

The usual dosage regimen in children is as follows:

Use in children:

Analgesia during operation, enhancement of anaesthesia with spontaneous respiration.

Techniques that involve analgesia in a spontaneous breathing child should only be used as part of an anaesthetic technique, or given as part of a sedation/analgesia technique with experienced personnel in an environment that can manage sudden chest wall rigidity requiring intubation, or apnoea requiring airway support.

It is important when estimating the required dose to assess the likely degree of surgical stimulation, the effect of premedicant drugs, and the duration of the procedure.

Obese patients:

In obese patients there is a risk of overdosing if the dose is calculated based on body weight. Obese patients should have dosage calculated according to their estimated ideal body mass.

Renal Impairment

Special precautions for disposal and other handling

CD(2), For IV or IM injection

If only part used, discard the remaining solution.