In deciding to receive a diagnostic test, the risks of taking the test must be weighed against the good it will do. This is a decision you and your doctor will make. For these tests, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to medicines in this group or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Children, especially those with other medical problems, may be especially sensitive to the effects of radiopaque agents. This may increase the chance of side effects.
Elderly people are especially sensitive to the effects of radiopaque agents. This may increase the chance of side effects.
Studies have not been done in humans with most of the radiopaque agents. However, iohexol, iopamidol, iothalamate, ioversol, ioxaglate, and metrizamide have not been shown to cause birth defects or other problems in animal studies. Some of the radiopaque agents, such as diatrizoates have, on rare occasions, caused hypothyroidism (underactive thyroid) in the baby when they were taken late in the pregnancy. Also, x-rays of the abdomen are usually not recommended during pregnancy. This is to avoid exposing the fetus to radiation. Be sure you have discussed this with your doctor.
Although some of these radiopaque agents pass into the breast milk, they have not been shown to cause problems in nursing babies. However, it may be necessary for you to stop breast-feeding temporarily after receiving a radiopaque agent. Be sure you have discussed this with your doctor.
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. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other Medical Problems
The presence of other medical problems may affect the use of diagnostic tests in this class. Make sure you tell your doctor if you have any other medical problems, especially:
- Acute kidney problems due to a severe liver disorder (hepato-renal syndrome [HRS]) or
- Acute kidney problems before, during, or after a liver transplant or
- Severe kidney problems, acute or chronic—The use of a gadolinium-based contrast agent (GBCA) should be avoided in patients with severe kidney problems. The risk of nephrogenic systemic fibrosis (NSF), a very serious disease affecting the skin, muscle, and internal organs, may be increased .
- Asthma, hay fever, or other allergies (history of)—If you have a history of these conditions, the risk of having a reaction, such as an allergic reaction to the radiopaque agent, is greater.
- High blood pressure (severe) or
- Pheochromocytoma (PCC)—Injection of the radiopaque agent may cause a dangerous rise in blood pressure.
- Liver disease—The radiopaque agent may build up in the body and cause side effects.
- Multiple myeloma (bone cancer)—Serious kidney problems may develop in patients with this condition.
- Overactive thyroid—A sudden increase in symptoms, such as fast heartbeat or palpitations, unusual tiredness or weakness, nervousness, excessive sweating, or muscle weakness may occur.
- Sickle cell disease—The radiopaque agent may promote the formation of abnormal blood cells.
- Type 2 diabetes mellitus—There is a greater risk of having kidney problems.