|Systematic (IUPAC) name|
|Pregnancy cat.||B3 (AU) C (US)|
|Legal status||Prescription Only (S4) (AU) ℞-only (CA) POM (UK) ℞-only (US)|
|Half-life||38 minutes (children), 60 minutes (adults)|
|Mol. mass||299.347 g/mol|
|(what is this?)|
Imipenem belongs to the subgroup of carbapenems. It is derived from a compound called thienamycin, which is produced by the bacterium Streptomyces cattleya. 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. Imipenem and other drugs in the carbapenem class are typically restricted in use, to avoid widespread bacterial resistance..
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 beta-lactamase (both penicillinase and cephalosporinase) produced by some bacteria, and is a strong inhibitor of beta-lactamases from some Gram-negative bacteria that are resistant to most beta-lactam antibiotics.
Spectrum of Bacterial Susceptibility and Resistance
Acinetobacter anitratus, Acinetobacter calcoaceticus, Actinomyces odontolyticus, Aeromonas hydrophila, Bacteroides distasonis, Bacteroides uniformis, and Clostridium perfringens species are generally susceptible to Imipenem, while some Acinetobacter baumannii, 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
Imipenem is rapidly degraded by the renal enzyme dehydropeptidase 1 when administered alone, and is always coadministered with cilastatin to prevent this inactivation (imipenem/cilastatin).
Common adverse drug reactions are nausea and vomiting. People who are allergic to penicillin and other beta-lactam antibiotics should take caution if taking imipenem, as cross-reactivity rates are low. At high doses, imipenem is actually seizuregenic.
- Kesado, Tadataka; Hashizume, Terutaka; Asahi, Yoshinari (1980). "Antibacterial activities of a new stabilized thienamycin, N-formimidoyl thienamycin, in comparison with other antibiotics". Antimicrobial agents and chemotherapy 17 (6): 912–7. PMC 283902. PMID 6931548.
- "Imipenem spectrum of bacterial susceptibility and Resistance". Retrieved 4 May 2012.
- Clissold, SP; Todd, PA; Campoli-Richards, DM (1987). "Imipenem/cilastatin. A review of its antibacterial activity, pharmacokinetic properties and therapeutic efficacy". Drugs 33 (3): 183–241. PMID 3552595.
- Buckley, MM; Brogden, RN; Barradell, LB; Goa, KL (1992). "Imipenem/cilastatin. A reappraisal of its antibacterial activity, pharmacokinetic properties and therapeutic efficacy". Drugs 44 (3): 408–44. PMID 1382937.