Carbapenem with maximum risk of seizures is:

Ans. (A) Imipenem(Ref: Goodman and Gilman 13th/e p1035)CarbapenemsThese include imipenem, doripenem, meropenem and ertapenem.These have wide spectrum of activity including gram positive cocci, gram negative rods as well as anaerobes.For the treatment of Pseudomonas (meropenem is most active whereas ertapenem is least) infections, these drugs should be combined with aminoglycosides.Carbapenems are b -lactamase resistant and are drugs of choice for Enterobacter, Klebsiella and Acinetobacter species.These are the only b -lactams which are reliably efficacious against ESBL (extended spectrum b-lactamase) producing organisms and are thus drug of choice for ESBL- producing bacteria.Main adverse effects of imipenem-cilastatin combination include seizures.Meropenem, doripenem and ertapenem are less likely to cause seizures.Ertapenem is very long acting and is inactive against Pseudomonas.