Foscarnet sodium is available as a 24-mg/mL solution of the drug (as the hexahydrate) in water for injection in 250-mL (6 g of foscarnet sodium hexahydrate) glass bottles.3022 Hydrochloric acid may have been added to adjust the pH.3022
pH
Adjusted to pH 7.4.3022
Sodium Content
Foscarnet sodium contains 5.5 mg of sodium per mL of solution.3022
Tonicity
Foscarnet sodium injection is isotonic.3022
Trade Name(s)
Foscavir
Foscarnet sodium is administered by intravenous infusion.3022 An infusion pump must be used for administration to prevent rapid infusion; the drug should not be administered by rapid or bolus intravenous injection.3022
Foscarnet sodium should only be infused into veins with adequate blood flow to allow for rapid dilution and distribution.3022 For peripheral administration, foscarnet sodium solution must be diluted to a concentration of 12 mg/mL with dextrose 5% or sodium chloride 0.9% to avoid local irritation of peripheral veins.3022 For administration through a central venous catheter, the 24-mg/mL solution may be infused undiluted.3022
Adequate hydration to establish diuresis is recommended in patients receiving foscarnet sodium provided there are no clinical contraindications.3022 It is recommended that patients receive hydration with 750 to 1000 mL of sodium chloride 0.9% or dextrose 5% prior to the first infusion of foscarnet sodium.3022 With subsequent infusions, hydration should be administered concurrently with each infusion of foscarnet sodium.3022 For foscarnet sodium doses of 90 to 120 mg/kg, 750 to 1000 mL of hydration fluid should be administered; for doses of 40 to 60 mg/kg, 500 mL of hydration fluid should be administered, although hydration may be decreased if clinically warranted.3022
Foscarnet sodium should be infused over at least 1 to 2 hours, depending upon the indication, dosage, and regimen (e.g., induction, maintenance).3022 The rate of infusion must not exceed 1 mg/kg/min.3022 Recommended dosage, frequency, and administration rates should not be exceeded.3022
Foscarnet sodium injection is a clear, colorless solution.3022 Intact bottles should be stored at controlled room temperature and protected from temperatures above 40°C and from freezing.3022 Refrigerated products or products exposed to temperatures below freezing may exhibit precipitation; however, the precipitate can be dissolved by bringing the bottle to room temperature and with repeated shaking.3022 The product should be used only if the bottle and seal are intact and a vacuum is present.3022
The manufacturer states that foscarnet sodium solutions diluted for infusion should be used within 24 hours of initial entry into a sealed bottle.3022
Foscarnet sodium may chelate divalent metal ions (e.g., calcium, magnesium) and is chemically incompatible with solutions containing calcium, such as Ringer’s injection, lactated, and parenteral nutrition solutions.3022
Foscarnet sodium (Astra) diluted to a concentration of 13 mg/mL in sodium chloride 0.9% and stored at 22°C did not exhibit an antibacterial effect on the growth of 3 organisms (Enterococcus faecium, Staphylococcus aureus, and Pseudomonas aeruginosa) that were inoculated into the solution. Foscarnet sodium exhibited moderate antifungal activity against Candida albicans. The authors recommended that ready-to-use solutions be stored under refrigeration whenever possible and that the potential for microbiological growth be considered when assigning expiration periods.2160
Autoclaving
The concentration of foscarnet sodium (Astra), diluted in sodium chloride 0.9% to a concentration of 12 mg/mL and packaged in glass infusion bottles with rubber bungs, was compared before and after autoclaving at 30 psi for 15 minutes at 121°C. The foscarnet sodium concentration did not change after autoclaving. Therefore, the dilution may be autoclaved to avoid limiting its shelf life due to sterility concerns.1835
Elastomeric Reservoir Pumps
Foscarnet sodium (Astra) 24 mg/mL was evaluated for binding potential to natural rubber elastomeric reservoirs (Baxter). No binding was found after storage for 2 weeks at 35°C with gentle agitation.2014
For a list of references cited in the text of this monograph, search the monograph titled References.