Carbenecillin

Antibiotic Class

Penicillin (carboxypenicillin)

Antimicrobial Spectrum

Gram positive bacteria:  Streptococcus spp., Listeria monocytogenes

Gram negative bacteria:  Pseudomonas aeruginosa, Enterobacter, Providencia, Morganella, Proteus, H. influenzae, E. coli, Proteus mirabilis, Salmonella spp., Shigella spp.

Mechanism of Action

Exerts bactericidal activity via inhibition of bacterial cell wall synthesis by binding one or more of the penicillin binding proteins (PBPs).  Exerts bacterial autolytic effect by inhibition of certain PBPs related to the activation of a bacterial autolytic process.

Pharmacodynamics

Penicillins produce time-dependent killing

Pharmacokinetics

Cmax: 223mcg/ml; Half-life: 1.1 hours; Table 6

Adverse Effects

Hematologic:  anemia, thrombocytopenia, neutropenia, agranulocytosis

CNS:  seizures

Renal:  nephrotoxicity, interstitial nephritis

Hepatic:  transient increases in transaminases

Other:  Jarisch-Herxheimer Reaction (fever, chills, sweating, tachycardia, hyperventilation, flushing, and myalgia)

Dosage

Adult: 382-764 mg po qid 

Pediatric: No data

Disease state based dosing:

Renal failure:  No data

Contraindications/Warnings/Precautions

Contraindications

Anaphylaxis to carbenecillin or other penicillins

Precautions

Cephalosporin hypersensitivity

Congestive heart failure or hypertension (the sodium content of high doses of parenteral carbenicillin should be considered in patients who require sodium restriction).

Drug Interactions

Contraceptives - decreased contraceptive effectiveness

Live Typhoid Vaccine - decreased immunological response to the typhoid vaccine

Probenecid - increased carbenecillin levels

Pregnancy

Category B: No evidence of risk in humans but studies inadequate.

Monitoring Requirements

Therapeutic:  Culture and sensitivities, signs and symptoms of infection

Toxic:  Periodic CBC, urinalysis, BUN, SCr, AST and ALT, diarrhea, skin rash

Brand names/Manufacturer 

CARBAPEN  (CSL - AUSTRALIA)

CARBECIN (Sanfer - MEXICO)

CARINDAPEN  (Pfizer - GERMANY)

GEOCILLIN (Pfizer - USA)

GEOPEN  (PFIZER INDIA, CANADA, HONG KONG, USA, ITALY, SPAIN)

MYCICLID  - (Wayne - MEXICO)

PYOPEN (WYETH - CANADA)

PYOPEN (Beecham FRANCE, CANADA, UK)

SAFEPEN  (Beecham - SPAIN)

UNIPEN (Pfizer - SPAIN)

UROCARF (SPA - ITALY)

UTICILLIN (Beecham Research, UK)