- meropenem is indicated for use in neonates at SJHC in the following instances:
- empiric therapy for seriously ill infants after standard therapy (aminoglycosides, ampicillin, ceftizoxime) has been considered and/or used.
- treatment of infections secondary to pathogens with documented resistance to first line antibiotics
- a consult to Infectious Diseases should be considered when using meropenem
- meropenem is a broad spectrum, beta-lactamase, carbapenem antibiotic for parenteral administration.
- meropenem is bactericidal; its activity results from inhibition of bacterial cell wall synthesis.
- meropenem possesses in-vitro activity against gram-positive aerobes, gram-negative aerobes and anaerobes.
- it does not possess good activity against methicillin - resistant Staphylococcus epidermidis or methicillin - resistant Staphylococcus aureus.,
- consult additional references for the sensitivity of specific organisms
- therapy may be started empirically before the results of sensitivity testing are the patient's clinical condition
- regular sensitivity testing is recommended when treating Pseudomonas aeruginosa infections.
- studies in premature neonates (n=14), full term neonates (n=10), infants (3 to 23 months, n=18) and children (2 to 12 years, n=25) demonstrated that following a 20 mg/kg dose the mean peak serum concentration was approximately 50 mcg/mL
- a 40 mg/kg dose (meningitic dose) produced a mean serum concentration of about 90 mcg/mL
- the half-lives in these age groups were as follows:
premature newborns - 3.0 h full term newborns - 2.0 h infants - 1.4 h children - 1.0 h
Plasma concentrations of meropenem for neonates, infants and children after a single dose of 20 or 40 mg/kg (Ped Infec Dis J 1997; 16:263-8)
- CSF concentrations are approximately 15% of the simultaneous serum concentrations during the first 1 to 4 h after IV infusion during the first 24 to 48 h of therapy in children with meningitis
- approximately 70% of a dose is recovered unchanged in the urine
- urinary concentrations in excess of 10 mcg/mL are maintained for at least 5 hours following a single dose
- there is 1 metabolite which is microbiologically inactive
- the following local and systemic adverse reactions were reported as possibly, probably or definitely related to meropenem in clinical trials:
- inflammation at injection site (2.4%)
- diarrhea (5% in pediatric patients)
- rash (1.2%)
- fever (0.2%)
- vaginal or oral moniliasis (0.2 - 0.4%)
- agitation, convulsions, neuropathy (<0.2%)
- constipation (<0.2%)
Changes in Laboratory Parameters (>0.2%)
- increased liver enzymes and bilirubin
- increased creatinine and BUN
- increased platelets (7% in pediatric patients)
- meropenem, like all beta-lactam antibiotics, has the potential to cause seizures (based on competitive inhibition of the inhibitory neurotransmitter, gamma-aminobutyric acid (GABA)); this risk may be increased in patients with decreased renal function and CNS lesions
- however, the degree to which a given beta-lactam antibiotic inhibits GABA differs; in an animal model imipenem was the most likely of the carbapenems to facilitate seizures, while meropenem was one of the least likely
- human studies have demonstrated equivalence in the incidence of seizures when meropenem and cefotaxime were compared
- for infants > 3 months - 20 mg/kg q8h
- for premature and term neonates we suggest a dose of 20 mg/kg q12h (at about 1 month of post-natal age it may be reasonable to consider a dosing interval of q8h)
- 40 mg/kg (dosing interval as described above)
- since about 70% of a dose is cleared unchanged by the kidney, consideration should be given to extending the dosing interval in cases of severely diminished renal function
- give by slow IV infusion over 30 minutes (10 mg/mL solution)
- if necessary may be given IV push over 3 to 5 minutes (50 mg/mL solution)
- 20 mg/mL syringe, prepared by Pharmacy Services
- available as a 500 mg vial (powder)
- to reconstitute add 10 mL NaCI 0.9% to prepare a 50mg/mL solution
- to dilute, add 4 mL of 50mg/mL solution (ie 100mg)to 6 mL 0.9% NaCI
Final Concentration =
200mg / 10mL
20 mg / mL
- Zenk KE, Sills JH and Koeppel RM : Neonatal Medications and Nutrition - A Comprehensive Guide, NICU INK Book Publishers, Santa Rosa, California, 1999.
- Bradley JS : Meropenem-a new, extremely broad spectrum beta-lactam antibiotic for serious infections in pediatrics, Pediatr Infect Dis J 1997;16;263-8.
- Gura KM : Intravenous drug administration guidelines for pediatric patients 1999, The Journal of Pediatric Pharmacy Practice, 1999;4:80-106.
- Merrem Product Monograph, Zeneca Pharma, Mississauga, Ontario, June 20,1996.