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Generic Name: Iohexol (eye oh HEX ole)
Brand Name: Omnipaque


  • Some products must not be given into the spine. Very bad and sometimes deadly health problems have happened when these products were given into the spine. This includes bleeding in the brain, coma, heart attack, kidney failure, paralysis, or seizures. Talk with the doctor.

Uses of Iohexol:

  • It is used before an x-ray or an alike test.

What do I need to tell my doctor BEFORE I take Iohexol?

All products:

  • If you have an allergy to iohexol or any other part of iohexol.
  • If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
  • If you are dehydrated, have been eating poorly, or have used a laxative or water pill before this medicine.
  • If you have had a skin reaction to iohexol or another drug like it in the past.
  • If you are taking metformin, talk with doctor.

Injection (if given into the spine):

  • If you have an infection.
  • If you are taking any drugs that may raise the chance of seizures, or if you have taken one in the last 48 hours. There are many drugs that can do this. Ask your doctor or pharmacist if you are not sure.

Injection (if given in the vein):

  • If you are not able to pass urine.

If used before an x-ray of the uterus and fallopian tubes:

  • If you are having your menstrual period or you have a genital infection.
  • If you have had a type of tissue taken out (curettage) or a type of cervix biopsy (conization) within the past 30 days.
  • If you have had a pregnancy ended within the past 6 months.
  • If you are pregnant or may be pregnant. Do not take this medicine if you are pregnant.

This is not a list of all drugs or health problems that interact with iohexol.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this medicine with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Iohexol?

All products:

  • Tell all of your health care providers that you take iohexol. This includes your doctors, nurses, pharmacists, and dentists.
  • Very bad and sometimes deadly allergic reactions have rarely happened. Talk with your doctor.
  • Your blood work may need to be checked. Talk with your doctor.
  • Thyroid problems have happened after use of this medicine. Some people had to be treated for these thyroid problems. Talk with the doctor.
  • A very bad and sometimes deadly reaction has happened with iohexol. Most of the time, this reaction has signs like fever, rash, or swollen glands with problems in body organs like the liver, kidney, blood, heart, muscles and joints, or lungs. Talk with the doctor.
  • If you have sickle cell disease, talk with your doctor.
  • This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take this medicine.
  • If you are 65 or older, use iohexol with care. You could have more side effects.
  • Use with care in children. Talk with the doctor.
  • Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using this medicine while you are pregnant.
  • Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.


  • Blood clots have happened with iohexol when used with some heart procedures. Sometimes, blood clots may cause heart attack and stroke, which may be deadly. Talk with the doctor.

Injection (if given into the spine):

  • This medicine may raise the chance of seizures in some people, including people who have had seizures in the past. Talk to your doctor to see if you have a greater chance of seizures while taking this medicine.

How is this medicine (Iohexol) best taken?

Use iohexol as ordered by your doctor. Read all information given to you. Follow all instructions closely.

All products:

  • You will need to be sure that you are not dehydrated before getting this medicine. Check with your doctor to see if you need to drink extra fluids before getting iohexol.
  • Drink lots of noncaffeine liquids after using this medicine unless told to drink less liquid by your doctor.


  • Your doctor will give iohexol.

Injection (if given into the spine):

  • Other drugs may be given before this medicine to help avoid side effects.


  • It may be given by mouth or given rectally.

What do I do if I miss a dose?

  • Call your doctor to find out what to do.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

All products:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Signs of kidney problems like unable to pass urine, change in how much urine is passed, blood in the urine, or a big weight gain.
  • A heartbeat that does not feel normal.
  • Very bad dizziness or passing out.
  • A very bad skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis) may happen. It can cause very bad health problems that may not go away, and sometimes death. Get medical help right away if you have signs like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in your mouth, throat, nose, or eyes.


  • Weakness on 1 side of the body, trouble speaking or thinking, change in balance, drooping on one side of the face, or blurred eyesight.
  • Chest pain or pressure.
  • This medicine may cause tissue damage if the drug leaks from the vein. Tell your nurse if you have any redness, burning, pain, swelling, blisters, skin sores, or leaking of fluid where the drug is going into your body.

Injection (if given into the spine):

  • Seizures.
  • Very bad headache.
  • Back pain.
  • Stiff neck.


  • Swelling.

What are some other side effects of Iohexol?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

All products:

  • Upset stomach or throwing up.


  • Headache.

Injection (if given in the vein):

  • Feeling of warmth.


  • Belly pain.
  • Loose stools (diarrhea).
  • Gas.
  • Feeling of warmth.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at

Side Effects (complete list)

If OVERDOSE is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Iohexol?

  • If you need to store iohexol at home, talk with your doctor, nurse, or pharmacist about how to store it.

Consumer Information Use and Disclaimer

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else's drugs.
  • Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
  • Talk with the doctor before starting any new drug, including prescription or OTC, natural products, or vitamins.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Check with your pharmacist about how to throw out unused drugs.
  • Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this medicine, please talk with your doctor, nurse, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

This information should not be used to decide whether or not to take iohexol or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to iohexol. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.

Review Date: December 6, 2017