Iodine Based X-Ray Contrast

What it is: Iodine-based contrast is a liquid. When injected into a vein for an x-ray examination, it allows enhanced visualization of blood vessels and other body parts.

Is it safe: Iodine-based contrast is very safe for most people.

Could I be allergic: While not a true allergy, injection of iodine-base contrast can cause allergic-like reactions which include itching, red rash (hives), wheezing, facial and throat swelling. This happens in 0.6% of people (60 in 10,000). Severe allergic like reactions occur in .04% of people (4 in 10,000). Death has been reported to occur in 0.0006% (1 in 170,000) people.

Are there other side effects: Other reactions that are not allergic-like include nausea, vomiting, headache, and vasovagal response (temporary drop in blood pressure and heart rate).

What will be done if I have a reaction:

• Mild: up to 3% people including allergic like (itching, mild red rash), and other reactions (nausea, vomiting and headache). Treatment is not typically needed for mild reactions.
• Moderate reactions include more severe rash (hives), severe vomiting, wheezing, facial swelling, throat swelling and drop in blood pressure and heart rate (vasovagal reaction). These reactions will be treated per established protocols, which may include oxygen, intravenous medications, inhaled medications. If response to treatment is not adequate, paramedics will be called to take you to the nearest hospital.
• Severe reactions that could be life-threatening are rare as noted earlier. Treatment will be initiated, and paramedics will be called.

What if I had a reaction to iodine-based contrast in the past: Please tell your doctor and tell us when you schedule your

exam. If you had an allergic-like reaction or don’t remember the type of reaction, your doctor will have to order premedication with steroids and possibly anti-histamines.

What if I have had reactions to shrimp and iodine preparations applied to the skin: These do not increase your risk of reaction to iodine-based contrast.

What if I have other allergies: While there is a small increase in risk of rection to iodine-based contrast, the American College of Radiology does not recommend any special precautions.

Do I need blood test measurement of kidney function? The American College of Radiology recommends assessment of kidney function for:

• Anyone with Any history of Any kidney disease
• Diabetics (optional)
• Use of Metformin containing medications.

Kidney function is measured with a simple blood test (creatinine) and should be done within 4 weeks of having an x-ray exam with iodine-based contrast. From the creatinine, the eGFR will be measured. If this number is great than 30, you may have your x-ray exam. If it is less than 30, there is an increased risk of further harming your kidneys. If this case, your exam will not be performed without permission of your doctor who will discuss the risks and benefits of having the x-ray exam with iodine-based contrast. You will be asked to hydrate well before and after your exam.