 MethodsDesign: The study is designed as a multi-centre randomised open-label active comparator-controlled non-inferiority trial, with a non-inferiority margin of 12. Eligible participants will be inpatients over the age of 21 with a CT or ultrasound scan suggestive of a liver abscess, and Klebsiella pneumoniae isolated from abscess fluid or blood. Randomisation into intervention or active control arms will be performed with a 1:1 allocation ratio. Participants randomised to the active control arm will receive IV ceftriaxone 2 grams daily to complete a total of 4 weeks of IV antibiotics. Participants randomised to the intervention arm will be immediately converted to oral ciprofloxacin 750mg twice daily. At week 4, all participants will have abdominal imaging and be assessed for clinical response CRP 20 mgl, absence of fever, plus scan showing that the maximal diameter of the abscess has reduced. If criteria are met, antibiotics are stopped; if not, oral antibiotics are continued, with reassessment for clinical response fortnightly. If criteria for clinical response are met by week 12, the primary endpoint of clinical cure is met. A cost analysis will be performed to assess the cost saving of early conversion to oral antibiotics, and a quality-of-life analysis will be performed to assess if treatment with oral antibiotics is less burdensome than prolonged IV antibiotics. 