Aztreonam is available in vials containing 1 or 2 g of the drug.2864; 2866 Aztreonam also is available in 1- and 2-g sizes as frozen premixed injection solutions in dextrose 3.4 and 1.4%, respectively, in single-dose Galaxy containers for intravenous infusion.2865 Both preparations contain approximately 780 mg of arginine per gram of aztreonam.2864; 2865; 2866
For intramuscular injection, each gram of aztreonam in vials should be reconstituted with at least 3 mL of one of the following diluents:2864; 2866
For intravenous bolus injection, vials should be used.2864; 2866 A vial should be reconstituted with 6 to 10 mL of sterile water for injection.2864; 2866
For intravenous infusion, a vial of aztreonam should be reconstituted with at least 3 mL of sterile water for injection per gram of aztreonam and further diluted with a compatible infusion solution.2864; 2866
On adding the diluent to the vial or bottle, the contents should be shaken immediately and vigorously.2864; 2866 Any unused portion of the reconstituted solution should be discarded.2864; 2866
The frozen premixed injection solutions also may be used for intravenous infusion after thawing at room temperature (25°C) or at 2 to 8°C.2865
pH
Aqueous solutions of aztreonam have pH values ranging from 4.5 to 7.5.2864; 2865; 2866
Sodium Content
Aztreonam is sodium free.2864; 2865; 2866
Trade Name(s)
Azactam
Aztreonam may be administered by intravenous injection or infusion2864; 2865; 2866 or by deep intramuscular injection into a large muscle mass.2864; 2866 By intravenous injection, the dose should be administered slowly, over 3 to 5 minutes, directly into a vein or into the tubing of a compatible infusion solution.2864; 2866 Intermittent infusion of aztreonam should be completed within 20 to 60 minutes.2864; 2865; 2866 If Y-site administration of aztreonam is employed, careful attention should be paid to ensure administration of the full intended dose.2864; 2866 A volume-control administration set may be used to dilute aztreonam in a compatible infusion solution during administration; however, the final concentration of aztreonam administered in such a way should not exceed 2% (w/v).2864; 2866
Intact vials should be stored at controlled room temperature; excessive heat should be avoided.2864; 2866 Exposure to strong light may cause yellowing of the powder.3310
Aztreonam solutions range from colorless to light straw to yellow.2864; 2865; 2866 They may develop a slight pink tint on standing without potency being affected.2864; 2866
Aztreonam solutions at concentrations of 2% (w/v) or less must be used within 48 hours if stored at controlled room temperature (15 to 30°C) or within 7 days at 2 to 8°C.2864; 2866 Solutions with concentrations exceeding 2% (w/v) should be used immediately after preparation unless sterile water for injection or sodium chloride 0.9% is used.2864; 2866 In these 2 excepted solutions, aztreonam at concentrations exceeding 2% (w/v) must be used within 48 hours if stored at controlled room temperature or within 7 days under refrigeration.2864; 2866
Concentration Effects
In one study, aztreonam dissolved in sterile water for injection to concentrations greater than 100 g/L resulted in unacceptably viscous solutions that impeded flow from elastomeric pumps to less than 75% of the nominal flow rate.3105
pH Effects
In aqueous solutions, aztreonam undergoes hydrolysis of the ß-lactam ring. Specific base catalysis occurs at pH greater than 6. At pH 2 to 5, isomerization of the side chain predominates. The lowest rates of decomposition occur at pH 5 to 7, with maximum stability occurring at pH 6.1072
Freezing Solutions
The commercially available frozen premixed injection solution should be stored in a freezer capable of maintaining the temperature at or below -20°C and should be thawed at room temperature (25°C) or at 2 to 8°C; solutions should not be refrozen.2865 After thawing, the container should be inverted to ensure that the solution is well mixed.2865 Solutions should not be subject to force thawing by immersion in water baths or microwaving.2865 The manufacturer indicates that thawed solutions are stable for 48 hours at room temperature (25°C) or for 14 days at 2 to 8°C.2865
Central Venous Catheter
Aztreonam (Squibb) 10 mg/mL in dextrose 5% was found to be compatible with the ARROWg+ard Blue Plus (Arrow International) chlorhexidine-bearing triple-lumen central catheter. Essentially complete delivery of the drug was found with little or no drug loss occurring. Furthermore, chlorhexidine delivered from the catheter remained at trace amounts with no substantial increase due to the delivery of the drug through the catheter.2335
Drugs in Syringe Compatibility
Y-Site Injection Compatibility (1:1 Mixture)
Additional Compatibility Information
Peritoneal Dialysis Solutions
Aztreonam (Bristol-Myers Squibb) was evaluated for stability at a concentration of 500 mg/L in Extraneal with icodextrin 7.5% (Baxter) and 400 mg/L in Nutrineal PD-4 with amino acids 1.1% (Baxter) at 6, 25, and 37°C protected from light.3563 The drug also was evaluated for stability in 2-compartment Physioneal with dextrose 1.36% (Baxter) and Physioneal with dextrose 2.27% (Baxter).3563 Bags of 2-compartment Physioneal with dextrose 1.36% and Physioneal with dextrose 2.27% contained aztreonam 1 g/L in one compartment (compartment composition unspecified) for storage at 6 and 25°C.3563 For bags of Physioneal with dextrose intended for storage at 37°C, the initial concentration of aztreonam in one compartment also was 1 g/L; however, the 2 compartments were combined immediately prior to storage at 37°C for a final aztreonam concentration of 500 mg/L.3563 Throughout the study, no color change or precipitation was noted on visual assessment.3563 In Extraneal with icodextrin 7.5%, aztreonam underwent little loss in 14 days at 6°C, less than 7% loss in 14 days at 25°C, and less than 4% loss in 24 hours at 37°C.3563 In Nutrineal PD-4 with amino acids 1.1%, aztreonam underwent about 7% loss in 14 days at 6°C, about 6% loss in 3 days at 25°C, and about 5% loss in 24 hours at 37°C.3563 In Physioneal with dextrose 1.36%, aztreonam in one compartment underwent about 3% loss in 14 days at 6°C and about 7% loss in 3 days at 25°C; with the compartments combined, aztreonam loss was about 6% in 2 hours at 37°C.3563 In Physioneal with dextrose 2.27%, aztreonam loss in one compartment was less than 6% in 14 days at 6°C and about 8% in 3 days at 25°C; with the compartments combined, aztreonam loss was about 7% in 1 hour at 37°C.3563
Aztreonam with cloxacillin sodium and aztreonam with vancomycin hydrochloride admixtures are stable in Dianeal 137 with dextrose 4.25% for 24 hours at room temperature.2864; 2866
For a list of references cited in the text of this monograph, search the monograph titled References.