What is the purpose of the Shilling's test?

The Shilling's test is specifically designed to assess the absorption of vitamin B12 in the body. It helps to determine if the body can adequately absorb this essential vitamin from the gastrointestinal tract. In the test, a patient is given a dose of radioactive vitamin B12 orally, followed by an injection of a non-radioactive form of vitamin B12. The amount of radioactivity in the urine is then measured to evaluate how much of the vitamin was absorbed. If absorption is impaired, it can indicate conditions such as pernicious anemia or other malabsorptive disorders affecting vitamin B12 uptake. Thus, the primary purpose of the Shilling's test aligns directly with the evaluation of vitamin B12 absorption.