Total iron binding capacity (TIBC) is a blood test that shows if there is too much or too little iron in the blood. This test helps measure the ability of a protein called transferrin to carry iron in the blood.

Blood is drawn from a vein, usually from the inside of the elbow or the back of the hand. The puncture site is cleaned with antiseptic. An elastic band is placed around the upper arm to restrict blood flow through the vein. This causes veins below the band to fill with blood.

A needle is inserted into the vein, and the blood is collected in an air-tight vial or an attached tube (syringe). The band is removed to restart blood flow. Once the blood has been collected, the needle is removed. The puncture site is covered to stop any bleeding.

For an infant or young child:

The area is cleansed with antiseptic and punctured with a sharp needle or a small pointed blade (lancet). The blood may be collected in a small glass tube (pipette), on a slide, onto a test strip, or into a small container. Cotton or a bandage may be placed on the puncture site if bleeding continues.

You should not eat or drink for 8 hours before the test.

When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging sensation. Afterward, there may be some throbbing.