Intravenous-to-Oral Switch (IVOS) Criteria

A switch should be initiated as soon as the patient is clinically stable and the oral route is viable.

Clinical Criteria for IVOS (The "HOME" Screen)

A patient is suitable for an oral switch if they meet all the following:

• H - Haemodynamically Stable: NEWS2 ≤2; heart rate and blood pressure normalising.
• O - Oral Route Reliable: Patient is eating/drinking with no malabsorption or vomiting.
• M - Markers Improving: Temperature <38°C for >24 hours; WCC and CRP trending toward normal.
• E - Exclude Deep-Seated Infection: No evidence of endocarditis, meningitis, or undrained abscess. See “Mandatory IV Exclusions” below for further details.

Mandatory IV Exclusions

The following infections require specialist consultation before switching to oral therapy:

• Staphylococcus aureus bacteraemia (plan for minimum 14 days IV, early IVOS only under specialist guidance).
• Deep-seated collections (e.g., liver abscess, empyema).
• Bone and joint infections (osteomyelitis, septic arthritis).

The following usually cannot be treated using oral agents:

• CNS infections, including meningitis, intracranial abscess, or encephalitis.
• Endocarditis and cardiac device-related infections.

IV-to-oral switch in improving patients with bacteraemia

• Blood stream infections with organisms other than S. aureus do not automatically preclude early IVOS.
• The origin of bacteraemia should be known and not require surgical source control.
• Switch to agents with high oral bioavailability is recommended.