Liposomal Amphotericin B Dosing for 63 kg Patient
For a 63 kg patient, administer liposomal amphotericin B at 3-5 mg/kg/day (189-315 mg/day) for standard invasive fungal infections, or 5-10 mg/kg/day (315-630 mg/day) for CNS involvement or severe mucormycosis. 1, 2
Standard Dosing by Indication
The specific dose depends entirely on the type and severity of fungal infection:
Standard Invasive Fungal Infections (3-5 mg/kg/day)
- Candidemia and invasive candidiasis: 3-5 mg/kg/day = 189-315 mg/day for your 63 kg patient 2
- Disseminated histoplasmosis (moderately severe): 3 mg/kg/day = 189 mg/day 2
- Candida chorioretinitis/endophthalmitis (fluconazole-resistant): 3-5 mg/kg/day = 189-315 mg/day 2
- Acute pulmonary histoplasmosis with respiratory complications: 3 mg/kg/day = 189 mg/day 2
CNS and Severe Infections (5-10 mg/kg/day)
- CNS candidiasis (meningitis): 5 mg/kg/day = 315 mg/day 2
- Cryptococcal meningitis: 4-6 mg/kg/day = 252-378 mg/day 3, 1
- Mucormycosis without CNS involvement: 5 mg/kg/day = 315 mg/day 3, 2
- Mucormycosis with CNS involvement: 10 mg/kg/day = 630 mg/day 3, 2
Critical Administration Points
Start with the full therapeutic dose on day 1—do not slowly escalate the dose over several days. 3 This is a common pitfall that delays achieving therapeutic drug levels.
Administer the entire daily dose once daily intravenously. 1, 4 The concentration-dependent fungicidal activity of amphotericin B supports once-daily dosing rather than divided doses. 3
Pre-medication and Supportive Care
Administer 1 liter of normal saline before and after the infusion to reduce nephrotoxicity in patients who can tolerate fluids. 1 This hydration strategy is critical for minimizing renal toxicity.
Pre-medicate with diphenhydramine or acetaminophen to reduce infusion-related reactions (fever, chills, nausea). 1, 4 If severe reactions occur during infusion (chest pain, dyspnea, severe abdominal pain, flushing, urticaria), temporarily interrupt the infusion and administer intravenous diphenhydramine. 1
Renal Impairment Considerations
Do not reduce the dose based on baseline renal impairment or elevated creatinine. 2 Liposomal amphotericin B is not significantly eliminated by the kidneys and does not accumulate in renal dysfunction. 2 This is a major advantage over conventional amphotericin B deoxycholate, which causes nephrotoxicity in up to 80% of patients. 2
If substantial nephrotoxicity develops during treatment, the dose can be reduced as necessary, but doses below 5 mg/kg/day are only marginally supported for severe infections. 3 The liposomal formulation causes significantly less nephrotoxicity than conventional amphotericin B. 3, 5
Monitoring Requirements
Monitor the following parameters regularly during therapy: 1, 2
- Serum creatinine
- Potassium levels (hypokalemia is common)
- Magnesium levels
- Liver function tests
Watch for infusion-related reactions including fever, chills, nausea, vomiting, chest pain, and dyspnea. 1, 4
Common Pitfalls to Avoid
Do not confuse liposomal amphotericin B with conventional amphotericin B deoxycholate. 2 The conventional formulation requires extreme caution in renal impairment and has much higher nephrotoxicity rates. 2, 5
Avoid concomitant nephrotoxic medications when possible (aminoglycosides, vancomycin, NSAIDs, contrast agents), as these increase the risk of additive renal injury even with the liposomal formulation. 2
Do not use doses below the recommended range for the specific indication, as this may compromise efficacy. 2 While some research suggests 1 mg/kg/day may be effective for certain indications 6, guideline-based dosing at 3-10 mg/kg/day depending on infection severity should be followed. 3, 1, 2
Pharmacokinetic Considerations
Recent data show considerable variability in drug exposure, with Cmax values of 20.0 mg/L at 3 mg/kg/day and 43.7 mg/L at 5 mg/kg/day in critically ill patients. 3 However, these values were not significantly different from healthy volunteers, suggesting that standard weight-based dosing is appropriate even in critically ill patients. 3
Neither dialysis nor hemofiltration reduces amphotericin B serum concentrations, so no supplemental dosing is needed post-hemodialysis. 3, 2