Adult 0.5-1 g 6-12 hrly. Max: 6 g daily.
Prophylaxis for infections during surgery 0.5 g 1 hr pre-op then 0.5 g during surgery, total dose of 1 g. Then 0.5-1 g 6-8 hrly daily for 5 days for post-op prophylaxis.
Childn >1 mth 25-50 mg/kg daily in divided doses & may increased to 100 mg/kg in severe infections.
Newborn 20 mg/kg 12 hrly. Doses are given by slow IM or IV inj over 3-5 or by IV infusion.