What volume of diluent is recommended to mix with Rocephin (Ceftriaxone) 2 grams for injection?

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Rocephin (Ceftriaxone) 2 Gram Reconstitution for Injection

For intramuscular injection, reconstitute Rocephin 2 grams with 7.2 mL of diluent to achieve a 250 mg/mL concentration, or with 4.2 mL to achieve a 350 mg/mL concentration. 1, 2

Intramuscular (IM) Preparation

The FDA-approved reconstitution volumes for a 2 gram vial are:

  • 7.2 mL of diluent → yields 250 mg/mL concentration 1, 2
  • 4.2 mL of diluent → yields 350 mg/mL concentration 1, 2

Acceptable Diluents for IM Administration

The following diluents may be used for intramuscular reconstitution 1, 2:

  • Sterile Water for Injection
  • 0.9% Sodium Chloride Solution
  • 5% Dextrose Solution
  • Bacteriostatic Water + 0.9% Benzyl Alcohol
  • 1% Lidocaine Solution (without epinephrine)

Administration Technique

  • Inject the diluent into the vial and shake thoroughly to form solution 1, 2
  • Withdraw entire contents of vial into syringe to equal total labeled dose 1, 2
  • Inject well within the body of a relatively large muscle 1, 2
  • Aspiration helps avoid unintentional injection into a blood vessel 1, 2

Intravenous (IV) Preparation

For intravenous administration, reconstitute the 2 gram vial with 19.2 mL of appropriate IV diluent, yielding approximately 100 mg/mL concentration. 1, 2

  • After reconstitution, withdraw entire contents and dilute to the desired concentration (10-40 mg/mL recommended) with appropriate IV diluent 1
  • Administer by infusion over 30 minutes in adults and children; 60 minutes in neonates to reduce risk of bilirubin encephalopathy 1, 2

Critical Safety Considerations

Do not use diluents containing calcium (such as Ringer's solution or Hartmann's solution) for reconstitution or further dilution, as particulate formation can result 1, 2

Stability After Reconstitution

IM solutions at 250 mg/mL or 350 mg/mL concentrations remain stable 1, 2:

  • Room temperature (25°C): 2 days (24 hours for bacteriostatic water or lidocaine solution)
  • Refrigerated (4°C): 10 days (3 days for 350 mg/mL concentration)

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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