How does contrast dye leave the body

The tube might also be connected to a small electric pump that will inject the ICCM. The most common way it is given is into a vein during a CT scan or into an artery for an angiogram. Most patients will notice a very warm feeling that spreads throughout their body for about 20 seconds during and after the injection.

This is often concentrated around the groin area and you might think that you are passing urine, but you are not. This is very common, very normal, nothing to worry about and the feeling goes away quickly 10—20 seconds. Some people feel nauseous like vomiting for a short time during and after the injection see the section on risks below. If you are given ICCM to drink, you generally will not notice any of the things described above.

The taste is not unpleasant, and you usually need to drink a couple of cups followed by some water. If you have ICCM into a tube in your rectum, it might feel temporarily uncomfortable, as if you need to go to the toilet. Most patients will not usually notice anything abnormal after being given ICCM. Some patients might have some allergies or side effects, which are discussed below. The ICCM will leave your body through your urine in the hours after your test or procedure.

You can help this by drinking plenty of fluids. If you are not allowed to drink due to your medical condition, the fluids will be given to you in an intravenous drip. This depends on the type of test or procedure you are having and how you are to be given the ICCM.

It is best to ask the staff this question when you are being prepared for your procedure. All medical tests, procedures and medications are associated with risks.

There are some risks that you need to know about before you have ICCM. If you know about these risks, and are in anyway concerned, then contact your doctor or the hospital or X-ray centre where you are having the test. You can do this when you make your appointment, and again when you arrive to have your test or procedure.

If there is a chance that you will be given ICCM, then you will be asked several questions at the time of your appointment or when you arrive for your test. These will include:. If you do not know the answers to these questions or are unsure, then your referring doctor should be able to help you. As with all medical procedures, the risks need to be weighed against the benefits in every case.

Your doctor will work with the radiologist to assess whether the risk of a procedure involving ICCM is outweighed by the benefits of the test. This is an individual medical judgment that is different for every patient and every situation or problem. Where the ICCM might provide additional information to the radiologist who is going to interpret your imaging the pictures taken when you have your X-ray procedure , this can often lead to a more accurate diagnosis that, in turn, will allow your doctor to better understand what is wrong and to give you the right treatment.

Reactions are unpredictable, and anyone can have a reaction. For this reason, all radiology practices and hospital radiology departments are prepared at all times to treat moderate and severe allergic reactions with appropriate medication. These reactions respond, in almost all cases, very well to emergency drug treatment. If you have had a mild, moderate or severe allergic reaction to ICCM in the past, you MUST tell the radiology facility when you are making your appointment.

If it is impossible to avoid giving ICCM, you might require medication tablets taken by mouth every few hours for several hours before the procedure to decrease the chance of you having a moderate or severe reaction. These tablets are corticosteroids or cortisone , which might reduce, but will not eliminate, the chance of another reaction to ICCM.

The tablets take a few hours to have any effect and do not work if you take them right before you have ICCM. Almost always these types of reactions do not require any special treatment and generally take only minutes to go away. Moderate reactions Moderate reactions consist of severe or prolonged vomiting, a generalised rash, or swelling of the face, mouth or throat, making it harder to breathe and swallow.

These reactions often need drug treatment, typically with adrenaline, antihistamines and sometimes corticosteroids or cortisone , as well as a period of observation 2—3 hours before you are allowed to go home. They occur in less than 1 in every people who has ICCM. Severe reactions Severe reactions are rare, and occur in less than 1 in every 25, people who have ICCM.

They require emergency medical treatment and admission to hospital for a period of observation. A severe reaction might consist of any of the following:.

These side effects are treated with emergency medication including adrenaline, and you will be admitted to hospital after this treatment for a period of monitoring. Less than 1 in every , people who have ICCM injected will die as a result of a very severe allergic-type reaction, even if emergency medical treatment is provided. NSF is a rare but serious disease affecting skin and other organs that has been found in some patients with advanced CKD after exposure to gadolinium-containing contrast dyes that are used in magnetic resonance imaging MRI.

People with acute kidney injury AKI are also at higher risk. NSF has not been reported in people with mild kidney damage or normal kidney function. NSF can be painful, debilitating, or even fatal. Symptoms and signs of NSF can include burning and itching of the skin, red or dark patches on the skin, joint stiffness, or muscle weakness.

The disease can develop within 24 hours up to around 3 months. MRIs are routinely used in patients to visualize internal organs and limbs to help detect and monitor many different diseases or injuries. Contrast dyes are often used during MRI to enhance the images obtained, and these dyes contain an element called gadolinium. In people with CKD, the kidneys are not able to filter out wastes, drugs and toxins the way they normally should.

In advanced CKD, the excretion of gadolinium-containing contrast dyes used in MRIs is slower than in people with normal kidney function. This delay in excretion is thought to be one the main reasons why NSF may happen. New medications are showing promising results but prevention remains key. There are benefits to undergoing these procedures. The benefits, however, should outweigh the risks associated with the use of contrast dye. These contrast dyes have helped in the diagnosis and treatment of many patients with various diseases and injuries, so there is also a risk of not doing these procedures.

If you would like more information, please contact us. While serious allergic or other reactions to contrast materials are rare, radiology departments are well-equipped to deal with them. Before arriving for you exam, you will be given specific instructions on how to prepare for the exam. Because contrast materials carry a slight risk of causing an allergic reaction or adverse reaction, you should tell your doctor about any of the following conditions.

These conditions could affect the instructions you are given. You should tell your doctor if these mild side effects of barium-sulfate contrast materials become severe or do not go away:. A very small percentage of patients may develop a delayed reaction with a rash which can occur hours to days after an imaging exam with an iodine-based contrast material.

Most are mild, but severe rashes may require medication after discussion with your physician. You should tell your doctor if these mild or moderate side effects of iodine-based contrast materials become severe or do not go away:. Patients with impaired kidney renal function should be given special consideration before receiving iodine-based contrast materials by vein or artery.

Such patients are at risk for developing contrast-induced nephropathy CIN , a condition in which already-impaired kidney function worsens within a few days of contrast material administration. Much of the research linking CIN with iodine-based contrast material is based on older contrast agents that are no longer used, and some recent studies have found no increased risk of CIN in patients who received iodine-based contrast material. If you have impaired kidney function, your doctor will assess the benefits of contrast-enhanced CT against any risks.

Some conditions increase the risk of an allergic or adverse reaction to iodine-based contrast materials. Being at increased risk for an allergic or adverse reaction to contrast material does not necessarily mean a patient cannot undergo an imaging exam with contrast materials.

Medications are sometimes given before the contrast material is administered to lessen the risk of an allergic reaction in susceptible patients. The contrast material used in MRI Magnetic Resonance Imaging called gadolinium is less likely to produce an allergic reaction than the iodine-based materials used for x-rays and CT scanning. Very rarely, patients are allergic to gadolinium-based contrast materials and experience hives and itchy eyes.

Reactions are usually mild and easily controlled by medication. Severe reactions are rare. Nephrogenic systemic fibrosis NSF , a thickening of the skin, organs, and other tissues, is a rare complication in patients with kidney disease that undergo an MR with contrast material. Gadolinium-based contrast material may be withheld in some patients with severe kidney disease. There is evidence that tiny traces of gadolinium may be retained in different organs of the body, including the brain, after contrast-enhanced MRI.

While there are no known negative effects from this, your doctor may take gadolinium retention into account when selecting a contrast agent. There are many different gadolinium-based contrast agents available, each with its own safety profile. Decisions on which material to use may be affected by the part of the body being imaged, the cost of the material and other factors. These decisions are especially important in patients likely to undergo multiple MRI scans with gadolinium-based contrast material, such as pediatric patients, cancer patients and people with multiple sclerosis.

If a barium-sulfate contrast material given orally or rectally will be used during your exam, you will be asked not to eat for several hours before your exam begins. If the contrast material will be given rectally, you may also be asked to cleanse your colon with a special diet and medication possibly including an enema before your exam.

If you swallow the contrast material, you may find the taste mildly unpleasant; however, most patients can easily tolerate it. If your contrast material is given by enema, you can expect to experience a sense of abdominal fullness and an increasing need to expel the liquid. The mild discomfort will not last long.

It is a good idea to increase your fluid intake after an imaging exam involving a barium-based contrast material to help remove the contrast material from your body.

Barium-sulfate contrast materials are expelled from the body with feces. You can expect bowel movements to be white for a few days. Some patients may experience changes in their normal bowel movement patterns for the first 12 to 24 hours.

When an iodine-based contrast material is injected into your bloodstream, you may have a warm, flushed sensation and a metallic taste in your mouth that lasts for a few minutes. The needle may cause you some discomfort when it is inserted. Once it is removed, you may experience some bruising. It is a good idea to increase your fluid intake after an imaging exam involving an iodine-based contrast material to help remove the contrast material from your body. When the gadolinium is injected, it is normal to feel coolness at the site of injection, usually the arm for a minute or two.

If you have not been sedated, no recovery period is necessary. You may resume your usual activities and normal diet immediately after the exam. Increased fluid intake will help eliminate the contrast material from your body. Prior to any imaging exam, women should always inform their physician or x-ray technologist if there is any possibility that they are pregnant.