indication

Used to treat serious gram–negative infections of the lungs, urinary tract, and skin.

pharmacology

Mezlocillin is a penicillin beta-lactam antibiotic used in the treatment of bacterial infections caused by susceptible, usually gram-positive, organisms. The name "penicillin" can either refer to several variants of penicillin available, or to the group of antibiotics derived from the penicillins. Mezlocillin has in vitro activity against gram-positive and gram-negative aerobic and anaerobic bacteria. The bactericidal activity of mezlocillin results from the inhibition of cell wall synthesis and is mediated through mezlocillin binding to penicillin binding proteins (PBPs). Mezlocillin is stable against hydrolysis by a variety of beta-lactamases, including penicillinases, and cephalosporinases and extended spectrum beta-lactamases. Mezlocillin can be used to treat susceptible strains of H. influenzae, Klebsiella species, Pseudomonas species, Proteus mirabilis, E. coli, Enterobacter species, Streptococcus faecelis, Peptococcus species, Peptostreptococcus species, Bacteriodes species (including B. fragilis), Morganella morganii, Serratia species, N. gonorrhoeae, P. vulgaris, and Providencia rettgeri. This drug is discontinued in the U.S.

mechanism of action

By binding to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, mezlocillin inhibits the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that mezlocillin interferes with an autolysin inhibitor.

toxicity

Symptoms of overdose include rash, fever, chills, and peeling skin.

biotransformation

Unlike many other penicillins, mezlocillin is either extensively metabolized or is subject to biliary excretion, as only about 50% of the dose was accounted for in normal urine.

half life

1.3 to 4.4 hours

drug interactions

Demeclocycline: Possible antagonism of action

Doxycycline: Possible antagonism of action

Ethinyl Estradiol: This anti-infectious agent could decrease the effect of the oral contraceptive

Methotrexate: The penicillin increases the effect and toxicity of methotrexate

Minocycline: Possible antagonism of action

Tetracycline: Possible antagonism of action