indication
For use in the treatment of the following infections when caused by susceptible strains of the designated microorganisms: (1) uncomplicated urinary tract infections caused by
Escherichia coli and
Proteus mirabilis, (2) otitis media caused by
Haemophilus influenzae (beta-lactamase positive and negative strains),
Moraxella catarrhalis (most of which are beta-lactamase positive), and
S. pyogenes, (3) pharyngitis and tonsillitis caused by
S. pyogenes, (4) acute bronchitis and acute exacerbations of chronic bronchitis caused by
Streptococcus pneumoniae and
Haemophilus influenzae (beta-lactamase positive and negative strains), and (5) uncomplicated gonorrhea (cervical/urethral) caused by
Neisseria gonorrhoeae (penicillinase- and non-penicillinase-producing strains).
pharmacology
Cefixime, an antibiotic, is a third-generation cephalosporin like ceftriaxone and cefotaxime. Cefixime is highly stable in the presence of beta-lactamase enzymes. As a result, many organisms resistant to penicillins and some cephalosporins due to the presence of beta-lactamases, may be susceptible to cefixime. The antibacterial effect of cefixime results from inhibition of mucopeptide synthesis in the bacterial cell wall.
mechanism of action
Like all beta-lactam antibiotics, cefixime binds to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, causing the inhibition of 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 cefixime interferes with an autolysin inhibitor.
toxicity
Symptoms of overdose include blood in the urine, diarrhea, nausea, upper abdominal pain, and vomiting.
biotransformation
Hepatic. Approximately 50% of the absorbed dose is excreted unchanged in the urine in 24 hours.
absorption
About 40%-50% absorbed orally whether administered with or without food, however, time to maximal absorption is increased approximately 0.8 hours when administered with food.
half life
3-4 hours (may range up to 9 hours). In severe renal impairment (5 to 20 mL/min creatinine clearance), the half-life increased to an average of 11.5 hours.