Мезлоциллин

Mezlocilin is an acylaminopenicillin, which has been shown to cause both immediate and delayed hypersensitivity in a nurse.

Like azlocillin, mezlocillin is used for infections of the urinary tract, gynecological infections, intraabdominal infections, skin infections, and respiratory tract infections. Synonyms of this drug are baypen, mezlin, and optocillin.

ChEBI: A penicillin in which the substituent at position 6 of the penam ring is a (2R)-2-[3-(methanesulfonyl)-2-oxoimidazolidine-1-carboxamido]-2-phenylacetamido group.

A semisynthetic acylureidopenicillin supplied as the sodium salt for parenteral administration.
Ampicillin-susceptible strains of H. influenzae and Neisseria spp. are very susceptible, but β-lactamase-producing organisms are usually resistant. It is less active than azlocillin and piperacillin against Ps. aeruginosa and has variable activity against B. fragilis, independent of β-lactamase production. It exhibits typical β-lactam synergy with aminoglycosides against Ps. aeruginosa and enterobacteria.
It attains peak concentrations of 250 mg/L after a 2 g intravenous infusion, with a plasma half-life of 55 min. Protein binding is 20–30%. It distributes into multiple tissues and human body fluids at therapeutically useful concentrations. Up to 60% of the dose is recoverable unchanged from the urine, with up to 2.5% excreted in the bile.
Toxicity and side effects are similar to those associated with carboxypenicillins. Its clinical use is for serious infections with susceptible organisms, including lower respiratory tract, intra-abdominal, urinary tract and gynecological infections. Commercial availability is quite limited.

Mezlocillin was synthesized by Bayer in 1974. The NH2 residue of ampicillin was acylated. Mezlocillin is a member of the so-called ureidopenicillins and shows two- to eightfold greater activity against Citrobacter, Enterobacter, Klebsiella, Escherichia coli, and Haemophilus influenzae than ampicillin, carbenicillin, or sulbenicillin. Its activity against gram-positive bacteria is almost the same as that of carbenicillin. Mezlocillin is used by intravenous administration for therapy of sepsis, meningitis, and respiratory tract, urinary tract, and abdominal infections.