Risks

The dyes (also called radio contrast media) are of 2 types: ionic and nonionic. Both types of dye contain iodine but differ in 2 key ways: the rate of adverse reactions and the cost.

Although the overall rate of adverse reactions is relatively low with both, there is a greater incidence of adverse reactions with the less expensive ionic dye than with the nonionic.

• Minor reactions, which are infrequent and do not last long, include flushing, nausea, vomiting, and itching.
  
  
• A small percentage of people experience a severe reaction to the dye, such as difficulty breathing, speaking, or swallowing; swelling of the lips and tongue; low blood pressure; or loss of consciousness. People who have had a severe reaction after receiving the dye once should not be exposed to it again.
  
  
• Pregnant women should not have an IVP because of the high radiation exposure.
  
  
• People with known kidney disease or failure should not have an IVP because the dye can worsen kidney function.
  
  
• Elderly people and those with diabetes, high blood pressure, heart disease, or evidence of dehydration are at risk of developing kidney failure following administration of the dye.
  
  
  • To avoid this complication, the kidney function should be tested with a blood test of the BUN (blood urea nitrogen) and creatinine, and the results should be known before the IVP is performed.
    
    
  • Those with diabetes and certain others (for example, women with polycystic ovarian syndrome) who are taking metformin (Glucophage) will have to discontinue this medication for 2 days after the IVP. They should inform their doctor of the test, and the doctor will coordinate their management during that time.