cloxacillin (Cloxapen, Tegopen)

Introduction

Tradename: Cloxapen. 2nd generation penicillin.

Indications

• antibiotic therapy for penicillinase-producing Staphylococcal infections
  • respiratory tract infections
    • upper respiratory tract infections
      • sinusitis
      • pharyngitis
    • lower respiratory tract infections
  • skin or soft tissue infections
  • infectious arthritis, osteomyelitis
  • urinary tract infection
  • endocarditis
  • septicemia
  • cholangitis
  • meningitis
• empiric treatment for fever of unknown origin

Contraindications

Caution:

• monitor PT in patients on warfarin
• elimination of drug is diminished with renal insufficiency
• use with caution in patients with cephalosporin allergy

pregnancy category = b

safety in lactation = ?

Dosage

• adults & children > 20 kg: 250-500 mg PO QID
• children (> 1 month & < 20 kg); 50-100 mg/kg/day PO divided every 6 hours

Tabs: 250 & 500 mg.

Liquid: (powder for oral suspension): 125 mg/5 mL.

Adverse effects

• not common (1-10%)
  • nausea, diarrhea
• uncommon (< 1%)
  • fever, rash, vomiting, eosinophilia, leukopenia, neutropenia, thrombocytopenia, agranulocytosis, hepatotoxicity, hematuria, serum-sickness like reaction

Drug interactions

• effect of oral contraceptives may be reduced
• disulfiram & probenecid may increase penicillin levels
• increased anticoagulant effect of warfarin

• drug interaction(s) anticonvulsants with anti-bacterial agents
• drug interaction(s) of antibiotics with warfarin

More general terms

• 2nd generation penicillin (penicillinase-resistant)

Database

• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=6098
• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=12557
• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=23477
• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=2813