Amphotericin B Stability and Administration

Availability

• Amphotericin deoxycholate 50mg (Photericin B and Amphotret)

Storage / Stability:

• Prior to reconstitution FUNGIZONE Intravenous should be stored in the refrigerator, protected against exposure to light.
• The concentrate (5 mg amphotericin B per mL after reconstitution with 10 mL Sterile Water for Injection, USP) may be stored in the dark, at room temperature for 24 hours, or at refrigerator temperatures for 1 week with minimal loss of potency and clarity.
• Any unused material should then be discarded. Solutions prepared for intravenous infusion (0.1 mg or less amphotericin B per mL) should be used promptly after preparation and should be protected from light during administration
• Reconstitute only with sterile water without preservatives, not bacteriostatic water.
• Benzyl alcohol, sodium chloride, or other electrolyte solutions may cause precipitation. 
• Label: REFRIGERATE.  

Alternative

• Short-term exposure (<24 hours) to light during I.V. infusion does not appreciably affect potency
• Reconstituted solutions with sterile water for injection and kept in the dark remain stable for 24 hours at room temperature and 1 week when refrigerated
• Stability of parenteral admixture at room temperature (25°C): 24 hours; at refrigeration (4°C): 2 days  

Test dose

• A single intravenous test dose (1 mg in 20 mL of 5% dextrose solution) administered over 20 to 30 minutes may be preferred.
• The patient’s temperature, pulse, respiration, and blood pressure should be recorded every 30 minutes for 2 to 4 hours

Administration

• An initial concentrate of 5 mg amphotericin B per mL is first prepared by rapidly expressing 10 mL Sterile Water for Injection, USP without a bacteriostatic agent directly into the lyophilized cake.
• Shake the vial immediately until the colloidal solution is clear.
• The infusion solution, providing 0.1 mg amphotericin B per mL, is then obtained by further dilution (1:50) with 5% Dextrose Injection, USP of pH above 4.2
• Administration recommendations:
• To be infused: 20-30 mins

Alternative administration

• Treatment dose:
• Dose <50 mg: further dilute in 500 ml of compatible diluents.
• Dose >50 mg: further dilute in 1 L of compatible diluents.
• To be infused: 2-6 hrs
• Max concentration:
• 0.1 mg/ml (peripheral)
• 0.25 mg/ml (central)

References:

1. Drug Information Leaflet
2. http://www.globalrph.com/ampho_B_dilution.htm