Ertapenem
254724
221719799
2008-06-25T19:56:57Z
68.34.45.74
/* Indications */ expanding acronym at first usage
{{drugbox
| IUPAC_name = (4''R'',5''S'',6''S'')-3-[(3''S'',5''S'')-5-[(3-carboxyphenyl)carbamoyl]<br>pyrrolidin-3-yl]sulfanyl-6-(1-hydroxyethyl)-4-methyl-7-<br>oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylic acid
| image = Ertapenem.svg
| CAS_number = 153832-46-3
| ATC_prefix = J01
| ATC_suffix = DH03
| ATC_supplemental =
| PubChem = 150610
| DrugBank = APRD00952
| C = 22 | H = 25 | N = 3 | O = 7 | S = 1
| molecular_weight = 475.516 g/mol
| bioavailability = 90% ([[intramuscular injection|intramuscular]])
| protein_bound = Inversely proportional to concentration; 85 to 95%
| metabolism = Minor [[hydrolysis]] of [[beta-lactam]] ring, [[cytochrome P450|CYP]] not involved
| elimination_half-life = 4 hours
| excretion = [[Kidney|Renal]] (80%) and fecal (10%)
| pregnancy_AU = B3
| pregnancy_US = B
| legal_status = Rx-only
| routes_of_administration = Intramuscular, [[intravenous therapy|intravenous]]
}}
'''Ertapenem''' is a [[carbapenem]] [[antibiotic]] marketed by [[Merck & Co.|Merck]] as '''Invanz'''. It is structurally very similar to [[meropenem]] in that it possess a 1-β-methyl group.
==Indications==
Ertapenem has been designed to be effective against [[Gram negative]] [[bacterium|bacteria]]. It is not active against [[MRSA]], [[ampicillin]]-resistant [[Enterococcus|enterococci]], ''[[Pseudomonas aeruginosa]]'' or ''[[Acinetobacter]]'' species. Ertapenem also has clinically useful activity against [[anaerobic bacteria]].
Ertapenem is marketed by Merck as a first-line treatment for community-acquired infections. It should not be used as empirical treatment for hospital-acquired infections because of its lack of activity against ''Pseudomonas aeruginosa''. In practice, it is reserved primarily for use against [[Extended spectrum beta-lactamase|Extended spectrum beta-lactamase (ESBL)]]-producing and high level [[AmpC]]-producing Gram-negative bacteria.
==Dosage==
Ertapenem is dosed as 1g given by [[intravenous]] injection over 30 minutes, or 1g diluted with 3.2ml of 1% [[lidocaine]] given [[intramuscular|intramuscularly]]. There is no [[Wiktionary:oral|oral]] preparation of ertapenem available. Ertapenem cannot be mixed with glucose.
The marketing [[slogan]] for ertapenem is "The Power of One", because the dose is one [[gram]], once a day.
==Pharmacology==
Unlike [[imipenem]] and [[meropenem]], ertapenem is highly protein bound, which explains its long half life (4 hours).
Ertapenem is [[excretion|excreted]] primarily (80%) by the kidneys. Metabolism by the liver is not clinically important and does not affect dosing.
Patients on [[haemodialysis]] should be given ertapenem at least 6 hours before dialysis. If it is given less than six hours before dialysis, then the patient should be given an additional dose of 150 mg IV after dialysis. Ideally, patients on haemodialysis should be given ertapenem immediately following dialysis.
===Resistance===
Acquired resistance to ertapenem is usually mediated by up-regulation of efflux mechanisms and by the selection of porin-deficient mutants. Organisms that produce a metallo-[[beta-lactamase|β-lactamase]] are innately immune to ertapenem (as well as all [[carbapenem]]s).{{Fact|date=October 2007}}
==Side effects==
There are few [[Adverse drug reaction|adverse effect]]s of ertapenem. The only absolute contra-indication is a previous [[anaphylaxis|anaphylactic reaction]] to ertapenem or other β-lactam antibiotic. There are no studies done in pregnant women, so the manufacturers cannot comment on its safety in pregnancy. In 2006, Ertapenem is now approved for pediatric use in certain infections. Ertapenem is not recommended for children under 3 months of age and children with meningitis.
Use of all antibiotics is associated with increased rates of [[antibiotic resistance|resistance]] (although carbapenem resistance is currently rare). There is particular worry that although ertapenem has no clinically useful activity against ''[[Pseudomonas aeruginosa]]'', widespread use of ertapenem could still lead to increased carbapenem resistance in ''Pseudomonas''.<ref>{{ cite journal
| author=Livermore DM, Mushtaq S, Warner M
| title=Selectivity of ertapenem for ''Pseudomonas aeruginosa'' mutants cross-resistant to other carbapenems
| journal=J Antimicrob Chemother
| year=2005
| volume=55
| issue=3
| pages=306–311
| doi= 10.1093/jac/dki009
| pmid=15705643
}}</ref>
Like many antibiotics, ''[[Clostridium difficile]]'' [[pseudomembranous colitis|colitis]] has been associated with its use.
==References==
{{reflist}}
{{CephalosporinAntiBiotics}}
{{Merck&Co}}
[[Category:Carbapenem antibiotics]]
[[es:Ertapenem]]