CARBAPENEM

Includes imipenem, Meropenem & Faropenem
Imipenem: Extremely potent & broad spectrum beta lactam antibiotic
Spectrum: gram positive coci, enterobacteriacae, P.aeruginosa, Listeria, as well as anaerobes like B. fragilis, cl. difficile
Resistant to most beta lactamases
It undergo rapid hydrolysis by the enzyme dehydropeptidase I located on the brush border of renal tubular cells
So it is combined with Cilastatin, a reversible inhibitor of dehydropeptidase I
ADR: GI upset, rashes & seizures at high dose
Indications: serious hospital acquired infections in neutropenic, cancer & AIDS pts
Meropenem: newer carbapenem
Not hydrolysed by renal dehydropeptidase I
Spectrum: broad spectrum similar to Imipenem
Indication: reserve drug for serious nosocomial infections caused by cephalosporin resistant bacteria
Less likely to cause seizures