Iobenguane I 123 (Intravenous)


When doctors suspect a patient has a certain medical condition, they will perform specific diagnostic tests in order to confirm whether or not the condition is present. Often, the appropriate diagnostic tests are determined by the patient's symptoms, clinical presentation, medical history and previous test results.

In order to make an accurate diagnosis, the results of each diagnostic test must be as detailed as possible. By using imaging tests, for example, physicians can obtain images from inside the patient's body and use these to determine whether particular health problems are present. In some cases, it is appropriate to use a radioactive agent during these diagnostic tests as they can increase clarity and accuracy.

When Iobenguane I 123 is used to assess problems with the adrenal glands, for example, the substance is administered to the patient and then adhered to adrenergic tissues. When viewed on a computer screen or on film, the contrast offered by Iobenguane I 123 enables physicians to determine if a tumor is present and, if so, exactly where it is and what size it is.

Similarly, if patients with congestive heart failure require further diagnostic testing, Iobenguane I 123 may be used. If the patient's condition has worsened or the exact cause of heart failure is undetermined, Iobenguane I 123 can highlight which area of the heart is failing to work properly. Based on the results of tests conducted with Iobenguane I 123, doctors can provide patients which a more thorough diagnosis and determine whether specific types of treatment would be suitable for them.

As Iobenguane I 123 is a radiopharmaceutical, it does carry some risks. When patients are given Iobenguane I 123, they are exposed to radiation and this can be harmful to their health. However, the benefit of a more accurate diagnosis and more appropriate treatment often outweighs the risk of a radiopharmaceutical being used during the relevant diagnostic tests.

Conditions Treated

  • Diagnostic agent for cancer of the adrenal glands and/or congestive heart failure

Type Of Medicine

  • Radiopharmaceutical

Side Effects

Although Iobenguane I 123 is used during the diagnostic process, rather than as a treatment, it can still cause patients to experience some side effects. After Iobenguane I 123 has been administered, for example, patients may notice the following adverse effects:

  • Blistering, soreness, tenderness, tingling or feeling of pressure at the injection site
  • Hives, bleeding, swelling, burning, rash or discoloration of the skin at the injection site
  • Coldness, bruising, infection, lumps, redness, scarring or warmth at injection site
  • Inflammation, warmth, itching, pain, numbness, ulceration or stinging at the injection site
  • Dizziness
  • Headache
  • Redness or feeling of warmth at the neck, face, arms, and sometimes, upper chest

If the patient displays the above side effects when being given Iobenguane I 123, they will not necessarily require medical treatment. If the side effects are not severe or troublesome to the patient, medical intervention may not be required. However, patients should always seek medical help if they experience severe side effects or if they are concerned about the presence of any adverse effects.

Furthermore, patients will need to seek immediate medical help if they experience the following side effects after being given Iobenguane I 123:

  • Difficulty swallowing or breathing
  • Unusual weakness or tiredness
  • Fast heartbeat
  • Tightness in the chest
  • Fever
  • Swelling of the face, eyes or inside of the nose
  • Hives
  • Reddening of the skin, particularly around the ears
  • Hoarseness
  • Rash on the skin
  • Irritation
  • Nausea
  • Joint swelling, stiffness or pain
  • Itching

If patients suffer from any other side effects once Iobenguane I 123 has been administered, they should also seek medical assistance.


Iobenguane I 123 is delivered intravenously and the patient will receive the medication via a needle placed in one of their veins. Due to this, patients will not have to calculate their own dose of Iobenguane I 123 or administer the medication themselves.

Typically, patients are given 10mCi of Iobenguane I 123 prior to diagnostic testing for cancer of the adrenal glands. Alternatively, patients with congestive heart failure may be given 10mCi, followed by 2mCi during calibration, if they are undergoing diagnostic testing.

However, every patient will be assessed individually and their dose will be calculated by a healthcare practitioner who has been trained in the use of radiopharmaceuticals.

Patients may be advised to consume a specific amount of liquid prior to Iobenguane I 123 being administered. This increases the frequency of urination and enables patients to pass the Iobenguane I 123 throughout their system more quickly. Patients may also be advised to urinate as often as possible in the 48 hours after Iobenguane I 123 has been administered. By excreting the substance as quickly as possible, the risk of potential damage being caused by Iobenguane I 123 can be reduced.

Potential Drug Interactions

As some medications interact with one another, it may not be appropriate for them to be used at the same time. For example, Iobenguane I 123 is not normally used in conjunction with the following medicines:

  • Albuterol
  • Imipramine
  • Amineptine
  • Ephedrine
  • Amitriptyline
  • Dothiepin
  • Amitriptylinoxide
  • Doxepin
  • Amoxapine
  • Dibenzepin
  • Bambuterol
  • Escitalopram
  • Guanethidine
  • Bupropion
  • Fluvoxamine
  • Butriptyline
  • Iprindole
  • Carvedilol
  • Nefazodone
  • Citalopram
  • Metaproterenol
  • Clomipramine
  • Milnacipran
  • Cocaine
  • Midodrine
  • Desipramine
  • Moclobemide
  • Desvenlafaxine
  • Norepinephrine
  • Duloxetine
  • Procarbazine
  • Epinephrine
  • Pseudoephedrine
  • Fluoxetine
  • Protriptyline
  • Furazolidone
  • Propizepine
  • Iproniazid
  • Reserpine
  • Isocarboxazid
  • Rasagiline
  • Isoproterenol
  • Phenelzine
  • Labetalol
  • Phenylephrine
  • Tianeptine
  • Phenylpropanolamine
  • Linezolid
  • Tranylcypromine
  • Pargyline
  • Lofepramine
  • Terbutaline
  • Melitracen
  • Sertraline
  • Methylene Blue
  • Selegiline
  • Nortriptyline
  • Trimipramine
  • Opipramol
  • Venlafaxine
  • Paroxetine

Although the use of Iobenguane I 123 alongside the above medications is not normally recommended, it may be necessary in some cases. If so, patients should notify their physician that they are using one of the above medications prior to the diagnostic test being carried out. In some cases, doctors may advise patients to alter their dose of medicine prior to diagnostic testing being carried out. However, patients should not stop taking their medicine or alter the dose unless they are advised to do so.

As some prescription medicines can also interact with over-the-counter medications, supplements and vitamins, patients should tell their physician if they are using any of these substances before they are given Iobenguane I 123. Similarly, patients will need to obtain medical advice before using any other medicines, supplements or vitamins once Iobenguane I 123 has been administered.


If patients have any existing health problems, they must disclose them to their physician before Iobenguane I 123 is used. Some conditions can affect the suitability of Iobenguane I 123 and these may include:

  • Kidney disease
  • Thyroid problems
  • High blood pressure (Hypertension)
  • Allergy or previous reaction to iodine, iodine-containing contrasting agents or any other iodine related products

Although Iobenguane I 123 may be used during diagnostic tests on pediatric patients, the safety of this medication has not been tested on infants under the age of one month in regard to testing for cancer of the adrenal glands. The safety of Iobenguane I 123 in diagnostic procedures performed on pediatric patients with heart problems has not been confirmed, regardless of their age. Due to this, Iobenguane I 123 is not usually prescribed to patients under the age of one month if they are due to undergo testing for adrenal gland problems and is not usually given to any pediatric patients if they are due to undergo testing for heart problems.

Iobenguane I 123 can be prescribed to geriatric patients but these patients may be more likely to suffer from existing age-related kidney problems. This may affect the suitability of Iobenguane I 123 and older patients may need a reduced dose of Iobenguane I 123.

Iobenguane I 123 contains benzyl alcohol which may cause serious reactions to infants with a low birth weight or premature infants. If patients or their parents, guardians or caregivers are concerned about the effects of Iobenguane I 123, they should discuss this with their physician prior to any diagnostic testing being carried out.

As a radiopharmaceutical, Iobenguane I 123 may cause fetal harm if it is administered to a pregnant patient. Due to this, patients who are pregnant should not be prescribed Iobenguane I 123, unless the benefits clearly outweigh the risks. Patients should be made aware of the risk to the unborn fetus prior to Iobenguane I 123 being used.

If patients breastfeed after being given Iobenguane I 123, it may cause harm to the infant. Due to this, patients are advised to stop breastfeeding if they have been treated with Iobenguane I 123. Patients will need to discuss this with their physician to determine when it is safe for them to resume breastfeeding after Iobenguane I 123 has been used to carry out diagnostic testing.

Before being given Iobenguane I 123, patients should tell their physician if they have any allergies, particularly if they are allergic to or have ever had a reaction to iodine, contrasting agents or iodine-containing substances. Iobenguane I 123 can cause patients to experience a serious allergic reaction, including anaphylaxis. If patients exhibit any of the following symptoms during or following treatment with Iobenguane I 123, they will require emergency medical treatment:

  • Chest pain
  • Rash on the skin
  • Difficulty breathing
  • Difficulty swallowing
  • Wheezing
  • Swelling of the tongue, face or throat
  • Itching
  • Hoarseness
  • Hives
  • Shortness of breath


In order to store this substance safely, the manufacturer's instructions should be followed carefully. Iobenguane I 123 is usually supplied in single-use vials and in lead containers. If lead is not used, an alternative form of radiation shielding should be provided. Generally, Iobenguane I 123 vials can be kept at room temperature but should only be handled by healthcare practitioner who are trained and qualified in the use of radioactive medicines.

As Iobenguane I 123 is only administered in a clinical setting, patients will not be required to store or dispose of this substance.


Although the use of radiopharmaceuticals, such as Iobenguane I 123, carries a risk for the patient, there are numerous benefits to using this substance during diagnostic testing. The clarity afforded by Iobenguane I 123 ensures that doctors are able to access clear images following diagnostic tests and can confirm the patient's condition with greater accuracy.

Due to this, Iobenguane I 123 is routinely used during testing for cancer of the adrenal glands or diagnostic testing in patients with congestive heart failure and is generally considered to be beneficial to the diagnostic process.