Carbapenems Flashcards
Imipenem-Cilastatin
time dependent bactericidal, but may be bacteriostatic against some bacteria
binds to most penicillin binding protein sites, inhibiting bacterial cell wall synthesis
cilastatin inhibits the metabolism of imipenem by DHP I on the brush borders of renal tubular cells which allows for higher concentration within urine and may protect against proximal tubular necrosis
activity against gram positive aerobic cocci (and some bacteriostatic against enterococci), gram positive aerobic bacilli, gram negative aerobic bacteria, many strains of pseudomonas and anaerobes; less active against gram negatives compared to meropenem; methicillin resistant staphylococci are resistant to imipenem
Most commonly used for extended spectrum against beta lactamase producing enterobacterales or pseudomonas
AE: GI, CNS (sz, tremors), hypersensitivity, infusion reactions
Rapid IV infusions may cause GI or CNS toxicity
Meropenem
Carbapenem that is used to provide broad coverage for both gram positive and gram negative infections, but especially useful in beta lactamase producing enterobacterales or pseudomonas
more active against enterobacterales and less so against gram positives when compared to imipenem
Methicillin-resistant Staphylococcus spp are resistant to carbapenems.
Meropenem is resistant to renal dehydropeptidase I (does not require inhibitor, cilastatin, like imipenem)
AE: usually well tolerated, SC - fur changes, in humans - mostly GI, but headache, skin rashes, and low risk of seizures possible
