Ferric hexacyanoferrate (Radiogardase) is used as an antidote that enhances the excretion of Cesium and Thallium from the body by binding to them in the gastrointestinal tract.

Ferric hexacyanoferrate (Radiogardase) Uses:

• Internal contamination:

  • It is indicated for the treatment of patients who have been contaminated or are suspected to have been contaminated with radioactive Cesium and radioactive or nonradioactive thallium.
  • The drug enhances the elimination of these agents.

Ferric hexacyanoferrate (Radiogardase) Dose in Adults

Ferric hexacyanoferrate (Radiogardase) Dose in the Internal contamination with radioactive cesium and/or radioactive or nonradioactive thallium: Oral:

Note:

• Treatment should begin as soon as possible following exposure to the radioactive material. Treatment may be given even if the therapy is delayed.
• The treatment typically continues for 30 days or more.

• Cesium exposure:

  • 1 to 3 g three times a day.
• Manufacturer's labeling:
  • The dosing recommended by the manufacturer may not reflect the current clinical practice.
  • 3.0 gms three times a day.

Ferric hexacyanoferrate (Radiogardase) Dose in Childrens

Ferric hexacyanoferrate (Radiogardase) Dose in Internal contamination with radioactive cesium and/or radioactive or nonradioactive thallium: Oral:

Note:

• Treatment should begin as soon as possible following exposure to the radioactive material but treatment may also be effective delayed.
• Treatment is typically continued for 30 days or more.
• Children 2 to 12 years:
  • 1 g thrice daily.
• Adolescents:
  • Refer to adult dosing.

Pregnancy Risk Factor C

• Animal reproduction studies have not included any study of the drug.
• The drug cannot be absorbed through the gastrointestinal tract. Therefore, it is unlikely that the drug will be absorbed into the maternal systemic circulation or fetal circulation.
• Cesium-137, Thallium and Thallium can cross the placental boundary and cause death in the fetus and malnutrition in the newborn.
• The radioactive materials (thallium, cesium) are expected to cause more toxicity than drug exposure. Treatment should be started immediately if necessary.
• If the mother is in danger or there is clear evidence, antidotes medications should be taken immediately.

Use during breastfeeding:

• It is unknown if the drug will be excreted into breast milk.
• It is not possible to absorb breastmilk and then have it excreted.
• Breast milk contains thallium and cesium. Breastfeeding should not be attempted by women who have radioactive agents in the bloodstream.

Dose in Kidney Disease:

There are no dosage adjustments provided in the manufacturer's labeling. The drug is not systemically absorbed.

Dose in Liver disease:

• There are no dosage adjustments provided in the manufacturer's labeling.
• However, because of decreased biliary excretion of cesium and thallium, the effectiveness of the drug may be decreased.

Side effects of Ferric hexacyanoferrate (Radiogardase):

• Gastrointestinal:

  • Constipation
  • Fecal discoloration (blue)
  • Fastric distress

• Endocrine & metabolic:

  • Hypokalemia

Contraindications to Ferric hexacyanoferrate (Radiogardase):

The manufacturer's label does not list any contraindications.

Warnings and precautions

• Discoloration

  • It can make your feces look blue.
  • Opened capsules can also cause discoloration of the oral mucosa or teeth.

• Cardiac arrhythmias:

  • The drug can cause electrolyte imbalances. The drug may cause cardiac arrhythmias in patients.
  • Patients with cardiac arrhythmias or pre-existing conditions should be advised to take the drug with caution.

• Electrolyte imbalances:

  • Electrolyte imbalances may be caused by the drug binding to them in the gastrointestinal tract.

• Gastric immotility

  • Patients who have reduced gastrointestinal motility and/or constipation should be cautious about taking the drug. 
  • Radiation absorption from the gastrointestinal tract may be increased by constipation.
  • Patients should be encouraged to consume more fiber or to use a laxative to help reduce constipation.

Monitoring parameters:

• Monitor bowel movements.
• Monitor CBC with differential counts, platelets, and electrolytes once a week.
• Monitor cesium and/or thallium exposure (whole-body counting and/or bioassay, feces, or urine sample) at baseline
• Monitor urinary and fecal cesium and/or thallium once a week during the treatment. Monitor residual whole-body radioactivity after a month of treatment.

How to administer Ferric hexacyanoferrate (Radiogardase)?

• The capsules may be opened or mixed with food or liquid and administered with food to stimulate the excretion of cesium and thallium.
• The concomitant ingestion of dietary fiber or fiber laxative may enhance its excretion.

Mechanism of action of Ferric hexacyanoferrate (Radiogardase):

• It decreases the absorption or radioactive residence time for cesium.
• This reduces radioactive material absorption and aids in their elimination via feces.

Absorption:

• Ferric hexacyanoferrate Oral: None

Half-life elimination:

• Cesium-137: Effective:
  • Adults: 80 days, decreased by 69% with ferric hexacyanoferrate;
  • adolescents: 62 days, decreased by 46% with ferric hexacyanoferrate;
  • children: 42 days, decreased by 43% with ferric hexacyanoferrate

Nonradioactive thallium: Biological: 8 days; with ferric hexacyanoferrate: 3 days

Excretion:

• Ferric hexacyanoferrate: Feces (99%, unchanged).

International Brand Names of Ferric hexacyanoferrate:

• Radiogardase
• Radiogardase-CS

Ferric hexacyanoferrate Brand Names in Pakistan:

No Brands Available in Pakistan.