Aztreonam is available as a powder in single-dose vials containing 1 or 2 g of the drug with approximately 780 mg of arginine per gram of aztreonam.2864
For intramuscular injection, each gram of aztreonam should be reconstituted with at least 3 mL of one of the following diluents:2864
For intravenous bolus injection, the contents of each vial should be reconstituted with 6 to 10 mL of sterile water for injection.2864
For intravenous infusion, each gram of aztreonam should be reconstituted with at least 3 mL of sterile water for injection and further diluted with a compatible infusion solution.2864
After adding the diluent, the vial should be shaken immediately and vigorously.2864 Any unused portion of the reconstituted solution should be discarded.2864
pH
Aqueous solutions of aztreonam have pH values ranging from 4.5 to 7.5.2864
Sodium Content
Aztreonam is sodium free.2864
Trade Name(s)
Azactam
Aztreonam may be administered by intravenous injection or infusion or by deep intramuscular injection into a large muscle mass.2864 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 Intermittent infusion of aztreonam should be completed within 20 to 60 minutes.2864 If Y-site administration of aztreonam is employed, careful attention should be paid to ensure administration of the full intended dose.2864 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
Intact vials should be stored at controlled room temperature; excessive heat should be avoided.2864 Exposure to strong light may cause yellowing of the powder.3310
Aztreonam is a white powder that forms a colorless to light straw yellow solution when reconstituted.2864 Solutions may develop a slight pink tint on standing without potency being affected.2864
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 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 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 at 2 to 8°C.2864
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
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
For a list of references cited in the text of this monograph, search the monograph titled References.