From the Research
To reconstitute 2g of Rocephin (ceftriaxone) for IM injection, use 7.2 mL of 1% lidocaine hydrochloride solution. This specific volume ensures proper dissolution of the medication while maintaining the appropriate concentration for intramuscular administration. When preparing the injection, add the lidocaine solution to the Rocephin vial and shake well until the powder is completely dissolved, resulting in a clear solution. The addition of lidocaine serves two purposes: it acts as a diluent for the antibiotic powder and helps reduce the pain associated with IM injection of ceftriaxone, which can be uncomfortable due to its concentration and pH.
The use of lidocaine as a diluent for ceftriaxone is supported by studies such as 1, which demonstrated that 1% lidocaine does not alter the elimination parameters or bioavailability of intramuscularly administered ceftriaxone. Additionally, the study found that the intensity and frequency of pain at the injection site were reduced considerably by the coadministered lidocaine. It's also important to note that other studies, such as 2, have shown that the tolerability and safety profiles of IM ceftriaxone therapy are comparable to those of other antibiotics, further supporting the use of lidocaine as a diluent.
It's essential to administer the reconstituted solution within 24 hours if stored at room temperature or within 3 days if refrigerated. Never use other lidocaine formulations containing preservatives or epinephrine for this purpose, as they may be incompatible with ceftriaxone. The pharmacokinetics of ceftriaxone, as described in studies such as 3 and 4, indicate that the drug is rapidly and completely absorbed following intramuscular administration, and the use of lidocaine as a diluent does not affect this process.
Some key points to consider when reconstituting and administering ceftriaxone include:
- Using the correct volume of lidocaine to ensure proper dissolution of the medication
- Avoiding the use of lidocaine formulations containing preservatives or epinephrine
- Administering the reconstituted solution within the recommended time frame
- Monitoring patients for any adverse reactions or interactions, as described in studies such as 5 and 2.