What the risks are:

There is a small risk to pregnant or nursing mothers, because the fetus or small child has a greater sensitivity to radioactive chemicals. Unless it is absolutely necessary, the scan will be delayed.

The amount of radiation is small (less than that of a conventional x-ray) and is virtually gone from the body within 1 or 2 days. With an increased number of scans, there is some radiation risk.

Special considerations:

Because this test is usually not performed unless there is acute pain, suspected gallbladder disease, or gallstones, many patients require urgent attention after the results of the test are known. Sometimes this test is combined with other imaging (such as CT or ultrasound). After the gallbladder scan the patient may be prepared for surgery, if it is necessary.