How much sodium is used when reconstituting 1 g of Rocephin (ceftriaxone) for IM injection?

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Sodium Content in 1 g Rocephin (Ceftriaxone) for IM Injection

1 gram of Rocephin (ceftriaxone) for IM injection contains approximately 83 mg (3.6 mEq) of sodium per gram of ceftriaxone activity. 1

Detailed Information About Ceftriaxone Sodium Content

The sodium content in ceftriaxone is important to know when administering this medication, particularly for patients who may be on sodium-restricted diets or those with conditions sensitive to sodium intake. According to the FDA drug label, ceftriaxone is formulated as a disodium salt, which contributes to its sodium content 1.

Chemical Composition

  • Ceftriaxone sodium is chemically described as (6R,7R)-7-[2-(2-Amino-4-thiazolyl)glyoxylamido]-8-oxo-3-[[(1,2,5,6-tetrahydro-2-methyl-5,6-dioxo-as-triazin-3-yl)thio]methyl]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, 72-(Z)-(O-methyloxime), disodium salt, sesquaterhydrate
  • Molecular weight: 661.60

Reconstitution Considerations for IM Administration

When preparing ceftriaxone for intramuscular injection, several factors should be considered:

Diluent Options

  • Standard diluent is sterile water for injection
  • Lidocaine hydrochloride (1%) can be used as a diluent to reduce injection pain 2
    • Studies have shown significantly reduced pain at the injection site when lidocaine is used as a diluent compared to sterile water 2

Administration Notes

  • Ceftriaxone IM injections are known to be painful 2
  • When reconstituted, the solution ranges from light yellow to amber, depending on concentration, storage time, and diluent used 1
  • Complete absorption occurs rapidly following intramuscular administration 3

Clinical Pharmacokinetics

Ceftriaxone has unique pharmacokinetic properties that make it suitable for once-daily dosing:

  • Exceptionally long elimination half-life (5.8-8.7 hours, mean 6.5 hours) 4, 3
  • After IM injection of 1g, mean peak plasma concentrations reach approximately 81 μg/mL 5
  • Plasma concentrations from IM administration become equivalent to IV administration by 2.5 hours post-dose 5
  • Distributes well throughout body spaces, including cerebrospinal fluid when inflammation is present 4

Important Considerations

  • The sodium content (83 mg/g) should be considered when treating patients with sodium restriction
  • No dosage adjustment is necessary for patients with renal dysfunction alone, but may be needed with combined hepatic and renal dysfunction 4
  • Ceftriaxone is not significantly removed by hemodialysis 3

This information is particularly relevant for clinicians who need to calculate total sodium intake for patients on restricted diets while ensuring appropriate antimicrobial therapy.

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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