(ampicillin sodium, sulbactam sodium)
General Dissolution Procedures
To reduce the development of drug-resistant bacteria and maintain the effectiveness of UNASYN and other antibacterial drugs, UNASYN should be used only to treat infections that are proven or strongly suspected to be caused by bacteria.
General Dissolution Procedures
UNASYN sterile powder for intravenous and intramuscular use may be reconstituted with any of the compatible diluents described for reconstitution in this insert. Solutions should be allowed to stand after dissolution to allow any foaming to dissipate in order to permit visual inspection for complete solubilization.
Preparation for Intravenous Use
1.5 g and 3 g Standard Vials:
- a)
- Reconstitute the vials with Sterile Water for Injection:
UNASYN Vial Size | Volume of Sterile Water for Injection for Reconstitution |
1.5 g | 3.2 mL |
3 g | 6.4 mL |
- •
- The reconstituted UNASYN solutions will have a total concentration of 375 mg/mL (ampicillin concentration of 250 mg/mL and sulbactam concentration of 125 mg/mL).
- •
- The resultant volume post reconstitution for the 1.5 g vials is approximately 4 mL and for the 3 g vials is approximately 8 mL.
- b)
- For intravenous infusion, immediately dilute with a suitable parenteral diluent (see Table 5) to yield solutions containing a total concentration between 3 mg/mL to 45 mg/mL of UNASYN (ampicillin concentration of 2 mg/mL to 30 mg/mL and sulbactam concentration of 1 mg/mL to 15 mg/mL).
Storage of Diluted UNASYN Solutions
Following dilution of reconstituted UNASYN, at the specified concentrations, the diluted solutions may be stored in the infusion bags based on conditions outlined in Table 5. After the indicated time periods, discard any unused portions of solutions.
| Diluent | Maximum Concentration (mg/mL) UNASYN (Ampicillin/Sulbactam) | Use Periods |
|---|---|---|
Sterile Water for Injection | 45 (30/15) 45 (30/15) 30 (20/10) | 8 hours at 25°C 48 hours at 4°C 72 hours at 4°C |
0.9% Sodium Chloride Injection | 45 (30/15) 45 (30/15) 30 (20/10) | 8 hours at 25°C 48 hours at 4°C 72 hours at 4°C |
5% Dextrose Injection | 30 (20/10) 30 (20/10) 3 (2/1) | 2 hours at 25°C 4 hours at 4°C 4 hours at 25°C |
Lactated Ringer's Injection | 45 (30/15) 45 (30/15) | 8 hours at 25°C 24 hours at 4°C |
M/6 Sodium Lactate Injection | 45 (30/15) 45 (30/15) | 8 hours at 25°C 8 hours at 4°C |
5% Dextrose in 0.45% Saline | 3 (2/1) 15 (10/5) | 4 hours at 25°C 4 hours at 4°C |
10% Invert Sugar | 3 (2/1) 30 (20/10) | 4 hours at 25°C 3 hours at 4°C |
1.5 g and 3 g Standard Vials
Reconstitute the vials with Sterile Water for Injection USP, 0.5% Lidocaine Hydrochloride Injection USP or 2% Lidocaine Hydrochloride Injection USP. Consult Table 6 for recommended volumes to be added to obtain solutions containing a total UNASYN concentration of 375 mg/mL (ampicillin concentration 250 mg/mL and sulbactam concentration 125 mg/mL).
Note: Use only freshly prepared solutions and administer within one hour after preparation.
| UNASYN Vial Size | Volume of Diluent to be Added | Withdrawal Volume* |
|---|---|---|
1.5 g | 3.2 mL | 4 mL |
3 g | 6.4 mL | 8 mL† |
To report SUSPECTED ADVERSE REACTIONS, contact Pfizer Inc. at 1-800-438-1985 or FDA at 1-800-FDA-1088 or http://www.fda.gov/ for voluntary reporting of adverse reactions.
This product's labeling may have been updated. For the most recent prescribing information, please visit www.pfizer.com.
LAB-0017-27.0
Revised November 2025
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