Intravenous means being positioned within, performed 
within, administered within, or occurring within a vein or 
veins. A vein is a blood vessel that carries blood to the 
heart. When a needle or catheter (flexible, hollow tube)  
goes inside a vein, this is an example of something that 
is intravenous. Some medical techniques, such as an 
inject a substance known as contrast which helps 
visualize the urinary tract. 
 
Mostly, intravenous access is used for therapeutic purposes, such as administering a 
medication (e.g., to treat cancer), administering fluids (e.g., in cases of dehydration) and  
performing a blood transfusion. Intravenous medication can be quickly pushed in with a 
syringe or it can be set to slowly drip in via a bag hanging from a pole connected to the 
catheter. 
Intravenous access may be preferred for several reasons including: a) the need to 
quickly get the medication into the bloodstream, and  b) the patient may not be able to 
swallow the medication for various reasons such as being a child, being placed on fluid 
restrictions, being unable to swallow while conscious (e.g., due to a sore throat), and 
being unable to swallow due to being unconscious. Intravenous is commonly abbreviated 
as I.V. or i.v. Intravenous is also known as endovenous. Intravenous comes from the 
Latin word "intra" meaning "within," and the Latin word "vena" meaning "vein."