(FER ik hex a SYE an oh fer ate)
- Ferric (III) Hexacyanoferrate (II)
- Ferric Ferrocyanide
- Insoluble Prussian Blue
- Prussian Blue
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Radiogardase: 0.5 g
Brand Names: U.S.
Binds to cesium and thallium isotopes in the gastrointestinal tract following their ingestion or excretion in the bile; reduces their gastrointestinal reabsorption (enterohepatic circulation)
Ferric hexacyanoferrate: Oral: None
Ferric hexacyanoferrate: Feces (99%, unchanged) (Radiogardase, 2008)
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
Special Populations: Hepatic Function Impairment
May be less effective because of decreased biliary excretion of cesium and thallium.
Use: Labeled Indications
Internal contamination: Treatment of patients with known or suspected internal contamination with radioactive cesium and/or radioactive or nonradioactive thallium to increase their rates of elimination.
There are no contraindications in the manufacturer’s labeling.
Internal contamination with radioactive cesium and/or radioactive or nonradioactive thallium: Oral: Note: Treatment should begin as soon as possible following exposure, but is also effective if therapy is delayed. Treatment typically continues for ≥30 days.
Manufacturer's labeling: 3 g 3 times daily
Alternative recommendations: Cesium exposure: 1 to 3 g 3 times daily (REMM, 2014)
Refer to adult dosing.
Internal contamination with radioactive cesium and/or radioactive or nonradioactive thallium: Oral: Note: treatment should begin as soon as possible following exposure, but is also effective if therapy is delayed. Treatment typically continues for ≥30 days.
Children 2 to 12 years: 1 g 3 times daily
Adolescents: Refer to adult dosing.
Dosing: Renal Impairment
There are no dosage adjustments provided in the manufacturer's labeling; however, ferric hexacyanoferrate is not systemically absorbed.
Dosing: Hepatic Impairment
There are no dosage adjustments provided in the manufacturer's labeling; however, effectiveness may be decreased due to decreased biliary excretion of cesium and thallium.
Capsules may be opened and mixed with bland food or liquid. Administer with food to stimulate excretion of cesium or thallium. Increase dietary fiber or take with fiber laxative to decrease constipation.
Take with food. A high-fiber diet or fiber laxative is recommended to avoid constipation.
Store at 20°C to 25°C (68°F to 77°F); excursions permitted between 15°C and 30°C (59°F and 86°F). Brief exposure to temperatures up to 40°C (104°F) may be tolerated provided the mean temperature does not exceed 25°C (77°F); however, minimize such exposure.
There are no known significant interactions.
Frequency not always defined.
Gastrointestinal: Constipation (24%), fecal discoloration (blue), gastric distress
Endocrine & metabolic: Hypokalemia (7%)
Concerns related to adverse effects:
• Discoloration: Feces will turn blue; if capsule contents are opened and eaten with food, oral mucosa and detention may also be colored blue.
• Cardiac arrhythmias: Use with caution in patients with preexisting cardiac arrhythmias; may cause electrolyte imbalances.
• Electrolyte imbalances: May bind to electrolytes in the GI tract. Use with caution in patients with electrolyte imbalances.
• Gastric immotility: Use with caution in patients with decreased gastric motility; constipation should be avoided to prevent increased radiation absorption from the gastrointestinal tract. Increase dietary fiber or take with fiber laxative to decrease constipation.
• Radiation exposure: Patients should be instructed to minimize radiation exposure to others or re-exposure to self.
• Radiation toxicity: Appropriate use: Ferric hexacyanoferrate increases the rate of elimination of thallium and cesium; it does not treat complications of radiation exposure. Supportive treatment for radiation toxicity should be given concomitantly. Additional decontamination and/or treatment may be needed if exposure to other radioactive isotopes is known or suspected.
Bowel movements; CBC with differential and platelets and electrolytes weekly
Baseline cesium and/or thallium exposure (whole body counting and/or bioassay, feces or urine sample); urine and fecal cesium and/or thallium weekly during therapy; residual whole body radioactivity after 30 days of treatment
Pregnancy Risk Factor
Animal reproduction studies have not been conducted. Ferric hexacyanoferrate is not absorbed from the gastrointestinal tract and is not expected to affect the fetus. Cesium-137 crosses the placenta; in one case, reported levels were equal in the mother and the neonate. Thallium also crosses the placenta; fetal death and failure to thrive have been reported. Toxicity from exposure to thallium or radioactive cesium is expected to be greater than the risk of toxicity to ferric hexacyanoferrate. In general, medications used as antidotes should take into consideration the health and prognosis of the mother; antidotes should be administered to pregnant women if there is a clear indication for use and should not be withheld because of fears of teratogenicity (Bailey, 2003).
• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
• Patient may experience mouth discoloration or stool discoloration. Have patient report immediately to prescriber signs of low potassium (muscle pain or weakness, muscle cramps, or an abnormal heartbeat), or severe constipation (HCAHPS).
• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.
Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.