imipenem imipenem imipenem (trade name primaxin among others) is an intravenous β-lactam antibiotic discovered by merck scientists burton christensen, william leanza, and kenneth wildonger in the mid-1970s. carbapenems are highly resistant to the β-lactamase enzymes produced by many multiple drug-resistant gram-negative bacteria, thus playing a key role in the treatment of infections not readily treated with other antibiotics. imipenemclinical datatrade namesprimaxinahfs/drugs.cominternational drug namesmedlineplusa686013license data us dailymed: imipenem pregnancycategory au: b3 routes ofadministrationim, ivatc codej01dh51 (who) legal statuslegal status au: s4 (prescription only) ca: ℞-only uk: pom (prescription only) us: ℞-only pharmacokinetic dataprotein binding20%metabolismrenalelimination half-life38 minutes (children), 60 minutes (adults)excretionurine (70%)identifiers iupac name (5r,6s)-6--3-(thio)-7-oxo-1-azabicyclohept-2-ene-2-carboxylic acid cas number64221-86-9 ypubchem cid104838drugbankdb01598 ychemspider4445535 yuniiq20im7he75keggd04515 ychebichebi:51799 ychemblchembl43708 ypdb ligandim2 (pdbe, rcsb pdb)comptox dashboard (epa)dtxsid2023143 echa infocard100.058.831 chemical and physical dataformulac12h17n3o4smolar mass299.35 g·mol−13d model (jsmol)interactive image smiles o=c(o)/c1=c(\scc/n=c/n)c2n1c(=o)2(o)c.o inchi inchi=1s/c12h17n3o4s.h2o/c1-6(16)9-7-4-8(20-3-2-14-5-13)10(12(18)19)15(7)11(9)17;/h5-7,9,16h,2-4h2,1h3,(h2,13,14)(h,18,19);1h2/t6-,7-,9-;/m1./s1 ykey:gsosvvulskvslq-jjvrhelesa-n y (verify) imipenem was patented in 1975 and approved for medical use in 1985. it was discovered via a lengthy trial-and-error search for a more stable version of the natural product thienamycin, which is produced by the bacterium streptomyces cattleya. thienamycin has antibacterial activity, but is unstable in aqueous solution, so impractical to administer to patients. imipenem has a broad spectrum of activity against aerobic and anaerobic, gram-positive and gram-negative bacteria. it is particularly important for its activity against pseudomonas aeruginosa and the enterococcus species. it is not active against mrsa, however. medical uses spectrum of bacterial susceptibility and resistance acinetobacter anitratus, acinetobacter calcoaceticus, actinomyces odontolyticus, aeromonas hydrophila, bacteroides distasonis, bacteroides uniformis, and clostridium perfringens are generally susceptible to imipenem, while acinetobacter baumannii, some acinetobacter spp., bacteroides fragilis, and enterococcus faecalis have developed resistance to imipenem to varying degrees. not many species are resistant to imipenem except pseudomonas aeruginosa (oman) and stenotrophomonas maltophilia. coadministration with cilastatin main article: imipenem/cilastatin imipenem is rapidly degraded by the renal enzyme dehydropeptidase 1 when administered alone, and is almost always coadministered with cilastatin to prevent this inactivation. adverse effects common adverse drug reactions are nausea and vomiting. people who are allergic to penicillin and other β-lactam antibiotics should take caution if taking imipenem, as cross-reactivity rates are high. at high doses, imipenem is seizurogenic. mechanism of action imipenem acts as an antimicrobial through inhibiting cell wall synthesis of various gram-positive and gram-negative bacteria. it remains very stable in the presence of β-lactamase (both penicillinase and cephalosporinase) produced by some bacteria, and is a strong inhibitor of β-lactamases from some gram-negative bacteria that are resistant to most β-lactam antibiotics.