Indication
Cloxacillin is indicated for the treatment of infections caused by Grampositive organisms including infections caused by ?ý-lactamase producing Staphylococci such as :
Skin and soft tissue infections : Boils, Abscesses, Carbuncles, Furunculosis, Cellulitis, Infected wounds, Infected burns, Otitis media and externa, Protection of skin graft and Skin infections like ulcer, eczema, acne, etc.
Respiratory tract infections : Pneumonia, Lung abscess, Empyema, Sinusitis, Pharyngitis and Tonsillitis.
Other infections caused by sensitive organisms : Osteomyelitis, Enteritis, Endocarditis, Urinary tract infection, Meningitis and Septicaemia.
Pharmacology
Cloxacillin inhibits bacterial cell wall synthesis by binding to 1 or more of the penicillin-binding proteins (PBPs) which in turn inhibit the final transpeptidation step of peptidoglycan synthesis in bacterial cell walls. Bacteria eventually lyse due to ongoing activity of cell wall autolytic enzymes (autolysins and murein hydrolases) while cell wall assembly is arrested.
Dosage
Upper Respiratory Tract Infection (Adult):
Usual Dose: 250 mg orally every 6 hours for 7 to 14 days, depending on the nature and severity of the infection.
Maximum dose: 4 g/day.
Upper Respiratory Tract Infection (Pediatric):
Usual Dose: The safety and efficacy of cloxacillin in children < 1 year have not been established.
? 1 year to 18 years: 50 to 100 mg/kg/day orally divided every 6 hours.
Maximum dose: 4 g/day.
Pneumonia?ÿ(Adult):
Usual Dose: 500 mg orally every 6 hours for up to 21 days, depending on the nature and severity of the infection.
Maximum dose: 4 g/day.
Pneumonia?ÿ(Pediatric):
Usual Dose: The safety and efficacy of cloxacillin in children < 1 year have not been established.
? 1 year to 18 years: 50 to 100 mg/kg/day orally divided every 6 hours.
Maximum dose: 4 g/day.
Skin and Structure Infection?ÿ(Adult):
Usual Dose: 500 mg orally every 6 hours for 7 days, or until 3 days after acute inflammation resolves, depending on the nature and severity of the infection.
Maximum dose: 4 g/day.
Skin and Structure Infection (Pediatric):
Usual Dose: The safety and efficacy of cloxacillin in children < 1 year have not been established.
? 1 year to 18 years: 50 to 100 mg/kg/day orally divided every 6 hours.
Maximum dose: 4 g/day.
Cystitis:
Usual Adult Dose: 250 mg orally every 6 hours for 3 to 7 days, depending on the nature and severity of the infection. Cloxacillin is rarely indicated for the treatment of cystitis.
Maximum dose: 4 g/day.
Interaction
May diminish the effect of BCG and typhoid vaccine. May increase risk of methotrexate toxicity. May diminish the therapeutic effect of Na picosulfate. May decrease serum concentrations of mycophenolate. May prolong bleeding time with anticoagulants. Increased serum concentrations with probenecid. Tetracycline may antagonise the bactericidal effect of cloxacillin.
Contradiction
Cloxacillin should not be given to patients known to be hypersensitive to penicillin.
Side Effect
Common side effects are skin rash, transient diarrhoea, nausea, heartburn, pruritus and disturbance of blood electrolyte. Rarely anaphylactic shock.
Pregnancy
Pregnancy?ÿCategory B.?ÿEither animal-reproduction studies have not demonstrated a foetal risk but there are no controlled studies in pregnant women or animal-reproduction studies have shown an adverse effect (other than a decrease in fertility) that was not confirmed in controlled studies in women in the 1st trimester (and there is no evidence of a risk in later trimesters).
Precaution
Cloxacillin should be given with caution to patients with known history ?ÿof allergy.
Overdose
Storage
Dry powder: Store below 25?ø C. Reconstituted solution: Store between 2-8?ø C (stable for 4 days); 23?ø C (stable for 24 hr).