What is IVOST?

Intravenous (IV) to oral switch therapy (IVOST) is the clinical process by which a patients antibiotic prescription is safely changed from an intravenous (IV) to oral regimen at the optimal time in light of clinical improvement and ascertainment of defined evidence-based criteria, preferably supported by easily accessible and clear guidelines within a multidisciplinary team approach to infection care.

This may involve switching to an antibiotic in the same or a different antibiotic class, depending on various clinical and microbiological factors. Historically, most IV antibiotic therapy was prescribed in hospitals so almost all of the published literature is within this context. Increasingly in recent decades, however, patients have been treated with IV antibiotic therapy in outpatient or community settings so consideration of the principles of IVOST in these settings is required. Week 1 will consider this.

In weeks 2 to 4, we will consider the monitoring of complex oral antibiotic regimens within the OPAT setting, often now referred to as complex oral and parenteral antibiotic therapy (COPAT) services. If you are unfamiliar with the principles and benefits of IVOST within the hospital setting, we suggest reading the article in the see also section below, which will be a useful primer.