Fungizone (Amphotericin B) - Drug Interactions, Contraindications, Overdosage, etc

DRUG INTERACTIONS

Drug Interactions

When administered concurrently, the following drugs may interact with amphotericin B:

Antineoplastic agents: may enhance the potential for renal toxicity, bronchospasm and hypotension. Antineoplastic agents (e.g., nitrogen mustard, etc.) should be given concomitantly only with great caution.

Corticosteroids and Corticotropin (ACTH): may potentiate amphotericin B-induced hypokalemia which may predispose the patient to cardiac dysfunction. Avoid concomitant use unless necessary to control side effects of amphotericin B. If used concomitantly, closely monitor serum electrolytes and cardiac function (see ADVERSE REACTIONS).

Digitalis glycosides: amphotericin B-induced hypokalemia may potentiate digitalis toxicity. Serum potassium levels and cardiac function should be closely monitored and any deficit promptly corrected.

Flucytosine: while a synergistic relationship with amphotericin B has been reported, concomitant use may increase the toxicity of flucytosine by possibly increasing its cellular uptake and/or impairing its renal excretion.

Imidazoles (e.g., ketoconazole, miconazole, clotrimazole, fluconazole, etc.): in vitro and animal studies with 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.

Other nephrotoxic medications: agents such as aminoglycosides, cyclosporine, and pentamidine may enhance the potential for drug-induced renal toxicity, and should be used concomitantly only with great caution. Intensive monitoring of renal function is recommended in patients requiring any combination of nephrotoxic medications (see PRECAUTIONS: Laboratory Tests).

Skeletal muscle relaxants: amphotericin B-induced hypokalemia may enhance the curariform effect of skeletal muscle relaxants (e.g., tubocurarine). Serum potassium levels should be monitored and deficiencies corrected.

Leukocyte transfusions: acute pulmonary toxicity has been reported in patients receiving intravenous amphotericin B and leukocyte transfusions (see PRECAUTIONS: General).

OVERDOSAGE

Amphotericin B overdoses can result in potentially fatal cardiac or cardiorespiratory arrest (see WARNINGS and DOSAGE AND ADMINISTRATION). If an overdose is suspected, discontinue therapy and monitor the patient’s clinical status (e.g., cardiorespiratory, renal, and liver function, hematologic status, serum electrolytes) and administer supportive therapy, as required. Amphotericin B is not hemodialyzable.

Prior to reinstituting therapy, the patient’s condition should be stabilized (including correction of electrolyte deficiencies, etc.).

CONTRAINDICATIONS

This product is contraindicated in those patients who have shown hypersensitivity to amphotericin B or any other component in the formulation unless, in the opinion of the physician, the condition requiring treatment is life-threatening and amenable only to amphotericin B therapy.