Intravenous antibiotics

Intravenous antibiotics are antibiotics delivered into a vein by injection or through a catheter.

Antibiotics are medicines that are used to treat or prevent bacterial infections. Antibiotics can be given by the following routes:

  • orally (by mouth) – tablets, capsule, liquid
  • topically (on your skin) – cream, ointment
  • by injection.

Your healthcare team will work out which route is the best for you. They will consider how severe your infection is and what types of bacteria are causing the infection.

When are antibiotic injections given?

Antibiotic injections may be given when:

  • your infection is severe and other routes may not work as well
  • you can't take oral antibiotics, for example because of being sick (vomiting)
  • the antibiotic treatment for the bacteria that is causing your infection can only be given by injection.

Injections can be given in different ways. The most common are into the vein (intravenous), muscle (intramuscular) or fatty tissue (subcutaneous). They are usually administered in hospital but can be administered at home. Read more about intravenous antibiotics at home.

How are intravenous (IV) antibiotics given?

The most common ways of giving an intravenous antibiotic are below.

Intravenous injection
An intravenous injection is an injection given over a few seconds or a few minutes. Intravenous injection is sometime called a bolus injection.

Intermittent infusion
An intermittent infusion is an injection given over 15 minutes or a few hours.

Continuous infusion
A continuous infusion is an injection given over 24 hours.

PICC line
Intravenous antibiotics can be given through a peripherally inserted central catheter known as a PICC line. This route is often used for patients needing intravenous antibiotics at home. Read more about PICC lines.

How long are intravenous (IV) antibiotics given for?

Your healthcare team will let you know how long you need to be on IV antibiotics. It will depend on how your infection is healing.


Antibiotics NHS Inform, UK

Credits: Health Navigator Editorial Team. Reviewed By: Sera Rahadi, Senior Clinical Pharmacist, Auckland City Hospital Last reviewed: 11 Feb 2022