Comparative Pharmacology
Head-to-head clinical analysis: CLOXACILLIN SODIUM versus POLYCILLIN N.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CLOXACILLIN SODIUM versus POLYCILLIN N.
CLOXACILLIN SODIUM vs POLYCILLIN-N
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Cloxacillin is a beta-lactam antibiotic that binds to penicillin-binding proteins (PBPs) located on the bacterial cell wall, inhibiting transpeptidases and thus preventing the cross-linking of peptidoglycan chains. This leads to cell lysis and death, primarily mediated by autolytic enzymes. It is resistant to penicillinase (beta-lactamase) produced by staphylococci.
Ampicillin is a beta-lactam antibiotic that inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs), disrupting peptidoglycan cross-linking, and activating autolytic enzymes. It is bactericidal against susceptible organisms.
250-500 mg orally every 6 hours on an empty stomach; 250 mg - 2 g IV/IM every 4-6 hours depending on severity; maximum 12 g/day for serious infections.
1-2 g IV/IM every 4-6 hours
None Documented
None Documented
0.5-1.1 hours in adults with normal renal function; prolonged in neonates, elderly, and renal impairment (up to 2-4 hours in anuria)
Terminal elimination half-life: 0.5-1 hour (normal renal function); increases to 7-10 hours in anuria. Prolonged in neonates (2-4 hours).
Renal (70-80% unchanged via glomerular filtration and tubular secretion); biliary/fecal (small amount, <10%)
Renal: 60-80% unchanged via glomerular filtration and tubular secretion. Biliary: ~20% excreted in bile and feces. Small amount metabolized to penicilloic acid.
Category A/B
Category C
Penicillin Antibiotic
Penicillin Antibiotic