From the Guidelines
The proper protocol for ordering amphotericin B involves specifying the exact formulation and dosing, with conventional amphotericin B deoxycholate typically dosed at 0.5--1.5 mg/kg administered once daily intravenously, as recommended by the CDC and the Infectious Diseases Society of America 1. When ordering amphotericin B, it is crucial to clearly indicate whether you're prescribing conventional amphotericin B deoxycholate or one of the lipid formulations, such as liposomal amphotericin B, amphotericin B lipid complex, or amphotericin B colloidal dispersion.
Key Considerations for Ordering Amphotericin B
- The recommended amphotericin B regimen is 0.5--1.5 mg/kg administered once daily intravenously, with the option to initiate at lower doses (0.25--0.5 mg/kg) in patients with mild-to-moderate disease and increase as tolerated 1.
- Amphotericin B should be administered in 5% dextrose in water to give a final concentration of 0.1 mg/mL and infused over 1--2 hours, with longer infusion times (3--6 hours) recommended for patients with azotemia, hyperkalemia, or those receiving high doses (>1 mg/kg) 1.
- Premedication with acetaminophen or diphenhydramine may alleviate febrile reactions, which are less frequent in children than adults 1.
- Laboratory monitoring orders for renal function, electrolytes (particularly potassium and magnesium), and complete blood counts should be included to mitigate the risk of nephrotoxicity and other adverse effects 1.
Special Considerations
- For patients with life-threatening disease, the target daily dose should be administered from the beginning, while those with mild-to-moderate disease may have their dose increased as tolerated 1.
- Amphotericin B lipid formulations may be considered for patients who are intolerant of conventional amphotericin B, have disseminated candidal infection that is refractory to conventional amphotericin B, or are at high risk for nephrotoxicity 1.
- The duration of therapy should be determined by the presence of deep tissue foci, patient clinical response, and presence of neutropenia, with treatment recommended until 2--3 weeks after the last positive blood culture and signs and symptoms have resolved for candidemia 1.
From the Research
Protocol for Ordering Amphotericin B
To order amphotericin B, the following steps should be considered:
- The usual daily maintenance dose of amphotericin B is 0.5-1 mg/kg i.v. 2
- The manufacturer recommends beginning intravenous therapy with a 1-mg test dose 2
- Amphotericin B can be infused over one to two hours (less than or equal to 50 mg/hr) in patients with adequate renal function 2
- Ancillary medications administered to treat infusion-related adverse events should be used as prophylaxis in patients with a history of hypersensitivity or unacceptable reactions and as needed for relief of symptoms 2
Preparation and Administration
When preparing and administering amphotericin B:
- Intravenous admixtures of amphotericin B 0.25 and 1.4 mg/mL in 5% dextrose injection have an expiration date of 35 days and 36 hours, respectively 2
- Admixtures should be stored at 4-8 degrees C, and protection from fluorescent light is unnecessary 2
- Admixtures may be prepared in polyolefin, glass, or polyvinyl chloride intravenous containers; certain evacuated intravenous containers contain buffers that can cause precipitation of amphotericin B 2
Considerations
It is essential to consider the following:
- Amphotericin B has been the standard of care for most invasive fungal infections, but its use is often associated with low efficacy and poor tolerance 3
- The antifungal armamentarium has increased with the addition of several new agents, including lipid formulations of amphotericin B, voriconazole, caspofungin, and micafungin 3
- The characteristics of these new agents, such as spectrum, pharmacokinetic profile, route of administration, efficacy in clinical trials, safety profile, drug-drug interactions, and cost, should be reviewed to help clinicians select an antifungal agent for their patients 3