Dilution of Ceftriaxone: 10 mL of Normal Saline per 1 gram
For intravenous administration, reconstitute 1 gram of ceftriaxone with 9.6 mL of 0.9% sodium chloride (normal saline), yielding approximately 10 mL total volume at a concentration of 100 mg/mL. 1
Reconstitution Details
The FDA-approved ceftriaxone labeling provides specific reconstitution volumes 1:
- 1 gram vial: Add 9.6 mL of diluent
- Final concentration: Approximately 100 mg/mL (1 gram in ~10 mL)
- 2 gram vial: Add 19.2 mL of diluent (also yields 100 mg/mL)
Further Dilution for IV Infusion
After initial reconstitution, withdraw the entire contents and further dilute to 50-100 mL of normal saline for IV infusion 1. The recommended concentration range is 10-40 mg/mL, though lower concentrations may be used if desired 1.
Standard Practice:
- Reconstitute 1 g with 9.6 mL → yields ~10 mL at 100 mg/mL
- Then dilute this in 50-100 mL normal saline for infusion
- Infuse over 30 minutes (60 minutes in neonates) 1
Critical Compatibility Warning
Never use calcium-containing diluents (Ringer's lactate, Hartmann's solution) with ceftriaxone, as particulate formation will result 1. Normal saline (0.9% sodium chloride) is the preferred and safest diluent 1.
Storage After Reconstitution:
Practical Considerations
Recent research confirms that 1 gram ceftriaxone diluted in 100 mL of 0.9% sodium chloride is an effective and commonly used preparation 2, 3. This concentration (10 mg/mL) falls within the recommended range and provides adequate stability when stored properly 1.
For intramuscular administration, different volumes apply (1.8-3.6 mL for 1 gram depending on desired concentration), but these are not relevant for IV use 1.