The main objective of this study is to investigate the non-inferiority of oral flucloxacillin alone compared with a combination of oral flucloxacillin and phenoxymethylpenicillin for the emergency department directed outpatient treatment of cellulitis, wound infections and abscesses, recently renamed by the Food and Drug Administration (FDA) as acute bacterial skin and skin structure infections (ABSSSIs). Half of the trial participants will receive flucloxacillin and placebo in combination, and the remaining half will be treated will flucloxacillin and phenoxymethylpenicillin.