Amphotericin

Amphotericin - is active against most fungi and yeasts. It also has useful activity against protozoa, including Leishmania spp., Naeglaria and Hartmanella. AmBisome is a formulation of amphotericin encapsulated in liposomes. This renders the drug less toxic to the kidney than the parent compound. Each vial contains 50 mg amphotericin.

Uses:
Severe systemic fungal infections, when conventional amphotericin is contraindicated because of toxicity, especially nephrotoxicity, or as a safer alternative to conventional amphotericin.

Administration
• IV: initially 1 mg/kg daily,↑if necessary to 3 mg/kg daily

Add 12 ml WFI to each 50-mg vial of liposomal amphotericin (4 mg/ml) Shake vigorously for at least 15 seconds
Calculate the amount of the 4 mg/ml solution required, i.e.:
100mg = 25 ml
150mg = 37.5 ml
200mg = 50 ml
300mg = 75 ml

Using the 5 micron filter provided add the required volume of the 4 mg/ml solution to at least equal volume of glucose 5% (final concentration 2 mg/ml) and given over 30–60 min

Although anaphylactic reactions rare, before starting treatment an initial test dose of 1 mg should be given over 10 min, infusion stopped and
patient observed for 30 min. Continue infusion if no signs of anaphylactic reaction
The diluted solution is stable for 24 hours
Monitor: serum potassium and magnesium
In renal dialysis patients, give AmBisome at the end of each dialysis Although nephrotoxic, no dose adjustment is required in haemofiltration

How not to use liposomal amphotericin:
Must not be given by rapid IV infusion (arrhythmias)
Not compatible with sodium chloride
Do not mix with other drugs
There are several formulations of IV amphotericin and they are not interchangeable. Errors of this sort have caused lethal consequences or subtherapeutic doses.

Adverse effects:
Prevalence and severity lower than conventional amphotericin

Cautions:
Kidney disease
Concurrent use of nephrotoxic drugs
Avoid concurrent administration of corticosteroids (except to treat febrile and anaphylactic reactions)
Diabetic patient: each vial contains 900 mg sucrose