In a New Zealand1 trial, in healthy volunteers, flucloxacillin 1000mg TDS with food got equivalent blood levels as in participants without food in their stomachs.
In New Zealand, flucloxacillin is only used in patients with skin infections or bacterial mastitis. For skin infections the recommended duration of treatment is now five days of treatment and for bacterial mastitis 5 to 7 days.
Caution is needed as this dosing with food has not been tested in sick patients and close monitoring may be warranted initially. Equally, the 500mg dose has not been tested.