In the U.S.—

• Diagnostic aid,Helicobacter pyloriinfection

Urea C 14 is a radiopharmaceutical (ray-dee-oh-far-ma-SOO-ti-kal ) . It is used to diagnose stomach ulcers caused by a certain kind of bacteria known as Helicobacter pylori or H. pylori.

This agent is taken by mouth. If any H. pylori bacteria are present in the stomach, they will cause the urea C 14 to be broken down into radioactive carbon dioxide gas. When you breathe out by the mouth, the amount of radioactive carbon dioxide can be measured to see whether the bacteria are in your stomach.

This agent is a radioactive agent. However, with the small amounts in the capsule that is used for the test, the radiation your body receives is very low and is considered safe.

This agent is to be given only by or under the direct supervision of a doctor with specialized training in nuclear medicine. It is available in the following dosage form:

Oral
• Capsules (U.S.)

In deciding to use a diagnostic test, any risks of the test must be weighed against the good it will do. This is a decision you and your doctor will make. Also, test results may be affected by other things. For this radiopharmaceutical, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to urea C 14. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Radiopharmaceuticals usually are not recommended for use during pregnancy. This is to avoid exposing the fetus to radiation. Some radiopharmaceuticals may be used for diagnostic tests in pregnant women, but it is necessary to inform your doctor if you are pregnant. Be sure you have discussed this with your doctor.

Breast-feeding—Some radiopharmaceuticals pass into the breast milk and may expose the baby to radiation. It is not known whether urea C 14 passes into breast milk. If you must receive a radiopharmaceutical, it may be necessary for you to stop breast-feeding for some time after receiving it. Be sure you have discussed this with your doctor.

Children—The amount of radiation in this agent is very low and considered safe for children. However, be sure you have discussed with your doctor the benefit versus the risk of exposing your child to radiation.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this radiopharmaceutical, it is especially important that your health care professional know if you are taking any of the following medications:

• Antibiotics or
• Medicines containing bismuth (e.g., Helidac Therapy, Pepto-Bismol)—May interfere with the results of the test; these medicines should not be taken within 4 weeks before the test

• Lansoprazole (e.g., Prevacid) or
• Omeprazole (e.g., Prilosec) or
• Sucralfate (e.g., Carafate)—May interfere with the results; these medicines should not be taken within 2 weeks before the test

• Stomach surgery—The lack of acid in the stomach may interfere with the results of this test

Do not eat or drink anything for 6 hours before having this test.

Do not touch the capsule with your hands because that could interfere with the test. The capsule will be handed to you in a cup. Tip the capsule directly into your mouth from the cup and swallow it with a little warm water.

Swallow the capsule whole. Do not crush or chew it before swallowing.

There are usually no special precautions to observe for radiopharmaceuticals when they are used in small amounts for diagnosis.

Along with its needed effects, a medicine may cause some unwanted effects. This agent does not usually cause any side effects. However, if you notice any unusual effects, check with your doctor.