ADMINISTRATION ROUTES:
IV
ALTERNATIVE NAMES:
AmBisome
ICU INDICATIONS:
-
Suspected or proven fungal infection (particularly after bone marrow transplant or in the setting of febrile neutropaenia)
-
Aspergillus infection
-
Cryptococcal meningitis
PRESENTATION AND ADMINISTRATION:
IV:
AmBisome for injection is a sterile, nonpyrogenic lyophilised product for IV infusion. Each vial contains 50 mg of amphotericin B, intercalated into a liposomal membrane. Following reconstitution with sterile water for injection, the resulting pH of the suspension is between 5-6. Add 12 mL of water for injection ONLY to vial. Immediately shake vial vigorously for 30 seconds to completely disperse powder (concentration = 4 mg/mL). Inspect for particulate matter and continue shaking until completely dispersed. Add required volume of reconstituted solution using 5-micron filter provided to 5% dextrose giving a concentration of 2 mg/mL (i.e. dilute one part reconstituted solution with one part 5% dextrose by volume). Infuse over 120 minutes (infusion time may be reduced to 60 minutes if the medication is well tolerated)
Store refrigerated at 2-8 degrees Celsius. Do not freeze. Reconstituted solution contains no preservative and should be refrigerated at 2-8 degrees Celsius and discarded 24 hours after preparation.
Compatible with 5% dextrose ONLY. Do not mix with other medications or IV fluids.
Aseptic technique must be strictly observed in all handling since no preservative or bacteriostatic agent is present in ambisome or in the materials specified for reconstitution and dilution.
DOSAGE:
IV:
Empirical therapy:
3.0 mg/kg/day
Systemic fungal infections due to Aspergillus, Candida, or Cryptococcus:
3-5 mg/kg/day. Always commence at 3.0 mg/kg/day and increase dose as required.
When this drug is administered for the first time an initial infusion of 10% of the total dose over 30 minutes should be given as a ‘test dose’. The remainder of the dose can then be administered over a further 120 minutes.
DOSAGE IN RENAL FAILURE AND RENAL REPLACEMENT THERAPY:
Dose as in normal renal function
DOSAGE IN PAEDIATRICS:
IV:
Empirical therapy:
3.0 mg/kg/day
Systemic fungal infections due to Aspergillus, Candida, or Cryptococcus:
3-5 mg/kg/day
Safety and effectiveness in paediatric patients below the age of 1 month have not been established.
CLINICAL PHARMACOLOGY:
Amphotericin B, the active ingredient of Ambisome, acts by binding to the sterol component of a cell membrane leading to alterations in cell permeability and cell death in susceptible fungi.
Ambisome has activity against the following organisms:
-
Aspergillus species (A. fumigatus, A. flavus)
-
Candida species (C. albicans, C. krusei, C. lusitaniae, C. parapsilosis, C. tropicalis)
-
Cryptococcus neoformans
-
Blastomyces dermatitidis.
CONTRAINDICATIONS:
- Known hypersensitivity to liposomal amphotericin
WARNINGS:
Anaphylaxis
Anaphylaxis has been reported with amphotericin. If a severe anaphylactic reaction occurs, the infusion should be immediately discontinued and the patient should not receive further infusions of ambisome.
PRECAUTIONS:
General:
A test dose is recommended (see DOSAGE)
Laboratory Tests:
No tests in addition to routine ICU tests are indicated
Drug/Laboratory Test Interactions: None known.
IMPORTANT DRUG INTERACTIONS IN ICU:
The following drugs are known to interact with amphotericin B and may interact with AmBisome:
Corticosteroids:
Concurrent use of corticosteroids may potentiate hypokalaemia
Digitalis Glycosides:
Concurrent use may induce hypokalaemia and may potentiate digitalis toxicity. Flucytosine:
Concurrent use of flucytosine may increase the toxicity of flucytosine by possibly increasing its cellular uptake and/or impairing its renal excretion.
Azoles:
In vitro and in vivo animal studies of the combination of amphotericin B and imidazoles suggest that imidazoles may induce fungal resistance to amphotericin B. Combination therapy should be administered with caution, especially in immunocompromised patients.
Leukocyte Transfusions:
Acute pulmonary toxicity has been reported in patients simultaneously receiving IV amphotericin B and leukocyte transfusions.
ADVERSE REACTIONS:
Body as a Whole:
Abdominal pain, back pain, chills, rigors
Cardiovascular System:
Chest pain, hypertension, hypotension, tachycardia
Respiratory System:
Cough increased, dyspnoea, epistaxis, hypoxia
Digestive System:
Diarrhoea, gastrointestinal haemorrhage, nausea, vomiting, hepatitis, cholestasis
Nervous System:
Anxiety, confusion, headache, insomnia
Skin:
Pruritus, rash
Urogenital System:
Renal impairment, haematuria
Metabolic:
Hypokalaemia, hypomagnesaemia