Pharmacokinetics and Proper Usage

Amphotericin B is available in the form of sterile lyophilized powder. Because it is insoluble in water, it is marketed with sodium deoxycholate for dispersal in sterile water and 5% dextrose. The polyene antibiotics — amphotericin B, nystatin, and candicidin — are all poorly absorbed from the gastrointestinal tract. In the plasma, amphotericin B binds to lipoproteins including cholesterol. It is extensively metabolized and the inactive metabolite, or metabolites, are slowly excreted in the urine. 

Amphotericin B is the only polyene antibiotic given parenterally. When the intravenous route is contemplated, amphotericin B is dispersed fresh, as discussed, and infused slowly. Amphotericin B should not be administered rapidly because this causes cardiac toxicity. Heparin (1000 units) is often added to the infusion suspension to avert the risk of thrombophlebitis. Amphotericin B can also precipitate normocytic or normochromic anemia, leukopenia, and thrombocytopenia. 

During the infusion of amphotericin B, the patient s temperature will rise, which may or may not be accompanied by hypotension and delirium. Often, hydrocortisone sodium succinate is added to the infusion during the initial but not the succeeding alternate-day treatment with amphotericin B. 

Amphotericin B is nephrotoxic in most patients and often causes a permanent reduction in the glomerular filtration rate. Furthermore, hypokalemia may occur, requiring the oral administration of potassium chloride. 

Amphotericin B injected intra-articularly to treat Coccidioidal Arthritis 

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