Drug information of Amphotericin B

Amphotericin B

Drug group:

Amphotericin b is an antifungal antibiotic . It works by killing the fungus and preventing its reproduction.

Mechanism of effect

Amphotericin Bacts by binding to the sterol component, ergosterol, of the cell membrane of susceptible fungi. It forms transmembrane channels leading to alterations in cell permeability through which monovalent ions (NA+, K+, H+, and Cl-) leak out of the cell resulting in cell death. While amphotericin B has a higher affinity for the ergosterol component of the fungal cell membrane, it can also bind to the cholesterol component of the mammalian cell leading to cytotoxicity.

Pharmacodynamic

Amphotericin Bacts by binding to the sterol component, ergosterol, of the cell membrane of susceptible fungi.

Pharmacokinetics

Distribution :Based on total amphotericin B concentrations measured within a dosing interval (24 hours), the mean half-life was 7-10 hours.
Metabolism :The metabolic pathways of amphotericin B are not known.
Excretion: The mean clearance at steady state was independent of dose. The excretion of amphotericin B has not been studied.

Dosage

Usual Adult Dose:
• Fungal Infection Prophylaxis :Prevention of invasive Candidiasis in solid-organ transplants: 10 to 20 mg per day IV
Prevention of invasive Candidiasis during periods of risk - ICU and Other Care Settings (stay of 3 days or longer): 0.25 mg/kg per day IV

• Aspergillosis – Aspergilloma :0.25 mg/kg per day IV
Daily dosage may be gradually increased to 0.5 to 1 mg/kg over a period of 2 to 4 days. Total doses range from 1 to 2 g.

• Aspergillosis – Invasive :0.5 to 0.6 mg/kg per day IV
Daily doses as high as 1 to 1.5 mg/kg have been suggested by some clinicians. Total doses of 1.5 to 4 g have been given over an 11-month period.

• Blastomycosis : 0.5 to 1 mg/kg per day IV
A total dose ranging from 1.5 to 2.5 g is needed for life-threatening disease. Patients with CNS infection should receive 0.7 to 1 mg/kg per day (total dose, at least 2 g).

• Candida Urinary Tract Infection : Candiduria: 0.3 to 1 mg/kg per day IV for 1 to 7 days Bladder irrigation: 5 to 50 mg/L instilled into the bladder for 60 to 90 minutes and drained 4

• Candidemia : Nonneutropenia: 0.6 to 1 mg/kg per day IV
Treatment duration should last 14 days after last positive blood culture and resolution of signs and symptoms.times a day for 2 to 5 days

• Neutropenia: 0.7 to 1 mg/kg per day IV
Treatment duration should last 14 days past last positive blood culture and resolution of signs and symptoms.

• Meningitis: 0.7 to 1 mg/kg per day IV plus flucytosine
Therapy should be administered for a minimum of 4 weeks after resolution of all signs and symptoms associated with the infection.

• Endocarditis: 0.6 to 1 mg/kg per day IV for at least 6 weeks after valve replacement; flucytosine may be used concomitantly
Chronic disseminated: 0.6 to 0.7 mg/kg per day IV
Treatment duration may last 3 to 6 months and resolution or calcification of radiologic lesions.

The addition of oral flucytosine may be considered for HIV-infected patients with invasive candidiasis.

• Coccidioidomycosis : Respiratory infection: 0.5 to 1 mg/kg per day IV to a maximum of 1.5 mg/kg per day for 4 to 12 weeks

• Coccidioidomycosis – Meningitis : 0.01 to 1.5 mg intrathecal injection
It is administered at intervals ranging from daily to weekly, beginning at a low dose and increasing until patient intolerance appears. Concomitant azole therapy is started.

• Cryptococcal Meningitis - Immunocompetent Host :0.7 to 1 mg/kg per day IV for 6 to 10 weeks
Therapy is given concomitantly with flucytosine.

• Cryptococcal Meningitis - Immunosuppressed Host : 0.7 to 1 mg/kg per day IV plus flucytosine for 2 weeks followed by fluconazole for a minimum of 10 weeks

• Cryptococcosis : Pulmonary: 0.5 to 1 mg/kg per day IV for 6 to 10 weeks
Total dose: 1 to 2 g
The addition of oral flucytosine may be considered.

• Esophageal Candidiasis : Severe and/or refractory esophageal candidiasis: 0.25 mg/kg per day IV
If tolerated, dosage may be gradually increased over 2 to 4 days to 0.3 to 0.7 mg/kg per day. Total doses range from 100 to 200 mg.
This drug should not be used to treat noninvasive fungal infections in patients with normal neutrophil counts.

• Fungal Endocarditis : 0.25 mg/kg per day IV
Dosage may be gradually increased to 1 to 1.5 mg/kg per day over a period of 2 to 4 days. Total doses range from 1.5 to 3 g.

• Histoplasmosis - Immunocompenent Host : Pulmonary: 0.7 mg/kg per day IV

• Histoplasmosis – Meningitis: 0.7 to 1 mg/kg per day IV to complete a 35 mg/kg total dose over 3 to 4 months

• Oral Thrush : Refractory or pharyngeal candidiasis: 0.25 mg/kg per day IV
Dosage may be gradually increased to 0.3 mg/kg per day over a period of 2 to 4 days.
Total doses range from 100 to 200 mg.
This drug should not be used to treat noninvasive fungal infections in patients with normal neutrophil counts.

• Paracoccidioidomycosis : 0.4 to 0.5 mg/kg per day IV to a maximum dose of 1.5 mg/kg per day in potentially fatal infections
Prolonged therapy is usually required.

• Sporotrichosis : 0.4 to 0.5 mg/kg per day IV for 2 to 3 months
Therapy has ranged up to 9 months with a total dose up to 2.5 g.

• Leishmaniasis :Treatment of American cutaneous leishmaniasis (caused by L braziliense or L mexicana: 0.25 to 0.5 mg/kg per day IV
Dosage may be gradually increased to 0.5 to 1 mg/kg daily, at which time the drug is usually then given on alternate days. Duration of treatment may last from 3 to 12 weeks depending on severity of disease. Total dose ranges from 1 to 3 g.

• Visceral Leishmaniasis : 0.5 to 1 mg/kg per day IV on alternate days for 14 to 20 doses Maximum dose: 50 mg per day
Total dose: 1.5 to 2 g

Usual Pediatric Dose
• Blastomycosis: 0.25 mg/kg per day IV
Total dose: greater than or equal to 30 mg/kg

• Candidemia : 0.6 to 1 mg/kg per day IV for 14 to 21 days after resolution of signs and symptoms and negative repeat blood cultures
The addition of oral flucytosine may be considered for HIV-infected patients with invasive candidiasis.

• Cryptococcal Meningitis - Immunosuppressed HostHIV-infected patient: 0.25 to 1 mg/kg per day IV

Alerts

Anaphylaxis has been reported with amphotericin B deoxycholate and other amphotericin B-containing drugs. If a severe anaphylactic reaction occurs, the infusion should be immediately discontinued and the patient should not receive further infusions of amphotericin B . As with any amphotericin B-containing product the drug should be administered by medically trained personnel. During the initial dosing period, patients should be under close clinical observation.

Points of recommendation

Some medical conditions may interact with amphotericin b. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you :
if you are pregnant, planning to become pregnant, or are breast-feeding
if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
if you have allergies to medicines, foods, or other substances and kidney problems

Pregnancy level

B

Related drugs

Flucytosine , Nystatin , Caspofungin


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