Intravenous therapy is treatment that infuses intravenous solutions, medications, blood, or blood products directly into a vein (Perry, Potter, & Ostendorf, 2014). Intravenous therapy is an effective and fast-acting way to administer fluid or medication treatment in an emergency situation, and for patients who are unable to take medications orally. 

The most common reasons for IV therapy (Waitt, Waitt, & Pirmohamed, 2004) include:

  1. To replace fluids and electrolytes and maintain fluid and electrolyte balance: The body’s fluid balance is regulated through hormones and is affected by fluid volumes, distribution of fluids in the body, and the concentration of solutes in the fluid. If a patient is ill and has fluid loss related to decreased intake, surgery, vomiting, diarrhea, or diaphoresis, the patient may require IV therapy.
  2. To administer medications, including chemotherapy, anesthetics, and diagnostic reagants: About 40% of all antibiotics are given intravenously.
  3. To administer blood or blood products: The donated blood from another individual can be used in surgery, to treat medical conditions such as shock or trauma, or to treat a failure in the production of red blood cells. The infusion restores circulating volumes, improving the ability to carry oxygen and replace blood components that are deficient in the body.
  4. To deliver nutrients and nutritional supplements: IV therapy can deliver some or all of the nutritional requirements for patients unable to obtain adequate amounts orally or by other routes.

SOURCE: https://opentextbc.ca/clinicalskills/chapter/intravenous-therapy-peripheral-and-central-venous-catheters/