Flucloxacillin
Indications
Flucloxacillin is used for:
Pneumonia, Burns, Meningitis, Endocarditis, Sinusitis, Septicaemia, Tonsillitis, Surgical Prophylaxis, Staphylococcal skin infections, Boils, Osteomyelitis, Enteritis, Wounds, Abscesses, Infected eczema, Infected acne
Adult Dose
Adults (including elderly patients):
Oral:
250-500mg 3-4 times a day.
Intravenous
IV 0.25-1 g 4 times/day, may double in severe cases. Up to 8 g/day in 3-4 divided doses may be given for osteomyelitis.
Up to 8 g/day in 4 divided doses for endocarditis in patients weighing <85 kg and 12 g/day in 6 divided doses for patients weighing >85 kg.
Child Dose
Children have been given doses of 12.5-25 mg/kg body weight 4 times a day.
Intravenous
2-10 years: Half of adult dose
Under 2 years: One fourth of adult dose
Renal Dose
Renal impairment:
CrCl (ml/min)
<10 Dosage adjustment may be necessary.
Administration
Should be taken on an empty stomach. Take on an empty stomach ½-1 hr before meals.
Reconstitution: Dissolve 250-500 mg in 5-10 mL water for inj or 1 g in 15-20 mL water for inj. For IV infusion, further dilute in suitable IV fluids (e.g. water for inj, NaCl 0.9%, glucose 5%, NaCl 0.18% w/ glucose 4%).
Contra Indications
Hypersensitivity to penicillins. Porphyria.
Precautions
Very high doses in poor renal function (risk of neurotoxicity) or heart failure. Avoid contact, skin sensitization may occur. Monitor serum potassium concentration, renal and haematological status. Spirochete infections particularly syphilis; suprainfection with penicillin-resistant organisms with prolonged use; avoid intrathecal route; elderly. Hepatic impairment.
Pregnancy-Lactation
Interactions
May increase the risk of methotrexate toxicity. May decrease the efficacy of oestrogen-containing OC. Enhanced plasma concentrations w/ probenecid. Bacteriostatic drugs (e.g. chloramphenicol, tetracycline) may interfere w/ the bactericidal effect of flucloxacillin. May prolong bleeding time in patients on oral anticoagulants.
Adverse Effects
Side effects of Flucloxacillin :
Hypersensitivity reactions including urticaria; fever; joint pains; rashes; angioedema; serum sickness-like reactions; haemolytic anaemia; interstitial nephritis; neutropenia; thrombocytopenia; CNS toxicity including convulsions; diarrhoea; antibiotic-associated colitis; hepatitis, cholestatic jaundice; agranulocytosis; phlebitis (IV infusion).
Potentially Fatal: Anaphylaxis. Stevens-Johnson syndrome
Mechanism of Action
Flucloxacillin inhibits the 3rd and last step of bacterial cell wall synthesis by binding to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall. It is active against penicillinase-producing and non-penicillinase-producing staphylococci.