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Ferric Citrate


(FER ik SIT rate)

Index Terms

  • Tetraferric Tricitrate Decahydrate

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Tablet, Oral:

Auryxia: Ferric iron 210 mg (ferric citrate 1 g) [contains fd&c blue #2 aluminum lake, fd&c red #40 aluminum lake, fd&c yellow #6 aluminum lake]

Brand Names: U.S.

  • Auryxia

Pharmacologic Category

  • Phosphate Binder


Lowers serum phosphate by binding to dietary phosphate in the GI tract; product precipitates as insoluble ferric phosphate and is excreted in feces.

Use: Labeled Indications

Hyperphosphatemia: For the control of serum phosphorus levels in patients with chronic kidney disease (CKD) receiving dialysis


Iron overload syndromes (eg, hemochromatosis)

Dosing: Adult

Note: Each tablet contains 210 mg of ferric iron equivalent to 1 g ferric citrate.

Hyperphosphatemia: Oral:

Initial: 2 tablets (420 mg ferric iron) 3 times daily

Maintenance: Increase or decrease dose by 1 tablet or 2 tablets (210 mg to 420 mg ferric iron) as needed at 1 week or longer intervals to achieve target serum phosphorus levels (maximum dose: 12 tablets [2,520 mg ferric iron] daily).

Dosing: Geriatric

Refer to adult dosing.

Dosing: Renal Impairment

There are no dosage adjustments provided in the manufacturer’s labeling.

Dosing: Hepatic Impairment

There are no dosage adjustments provided in the manufacturer’s labeling.


Oral: Administer with meals.

Dietary Considerations

Take with meals. Ensure adherence with prescribed diet.


Store at 20°C to 25°C (68°F to 77°F); excursions are permitted between 15°C and 30°C (59°F and 86°F). Protect from moisture.

Drug Interactions

Alpha-Lipoic Acid: Iron Salts may decrease the absorption of Alpha-Lipoic Acid. Alpha-Lipoic Acid may decrease the absorption of Iron Salts. Consider therapy modification

Bisphosphonate Derivatives: Iron Salts may decrease the serum concentration of Bisphosphonate Derivatives. Management: Avoid administration of oral iron supplements within: 2 hours before or after tiludronate/clodronate/etidronate; 60 minutes after oral ibandronate; or 30 minutes after alendronate/risedronate. Exceptions: Pamidronate; Zoledronic Acid. Consider therapy modification

Cefdinir: Iron Salts may decrease the serum concentration of Cefdinir. Red-appearing, non-bloody stools may also develop due to the formation of an insoluble iron-cefdinir complex. Management: Avoid concurrent cefdinir and oral iron when possible. Separating doses by several hours may minimize interaction. Iron-containing infant formulas do not appear to interact with cefdinir. Consider therapy modification

Deferiprone: Iron Salts may decrease the serum concentration of Deferiprone. Management: Separate administration of deferiprone and oral medications or supplements that contain polyvalent cations by at least 4 hours. Consider therapy modification

Dimercaprol: May enhance the nephrotoxic effect of Iron Salts. Avoid combination

Dolutegravir: Iron Salts may decrease the serum concentration of Dolutegravir. Management: Administer dolutegravir at least 2 hours before or 6 hours after oral iron. Alternatively, dolutegravir and oral iron can be taken together with food. Consider therapy modification

Eltrombopag: Iron Salts may decrease the serum concentration of Eltrombopag. Management: Administer eltrombopag at least 2 hours before or 4 hours after oral administration of any iron-containing product. Consider therapy modification

Ferric Hydroxide Polymaltose Complex: May decrease the serum concentration of Iron Salts. Specifically, the absorption of oral iron salts may be reduced. Management: Do not administer intravenous (IV) ferric hydroxide polymaltose complex with other oral iron salts. Therapy with oral iron salts should begin 1 week after the last dose of IV ferric hydroxide polymaltose complex. Consider therapy modification

Levodopa: Iron Salts may decrease the serum concentration of Levodopa. Only applies to oral iron preparations. Management: Consider separating doses of the agents by 2 or more hours to minimize the effects of this interaction. Monitor for decreased therapeutic effects of levodopa during concomitant therapy, particularly if doses cannot be separated. Consider therapy modification

Levothyroxine: Iron Salts may decrease the serum concentration of Levothyroxine. Management: Separate oral administration of iron salts and levothyroxine by at least 4 hours. Separation of doses is not required with parenterally administered iron salts or levothyroxine. Consider therapy modification

Methyldopa: Iron Salts may decrease the serum concentration of Methyldopa. Consider therapy modification

PenicillAMINE: Iron Salts may decrease the absorption of PenicillAMINE. Only oral iron salts are a concern. Consider therapy modification

Phosphate Supplements: Iron Salts may decrease the absorption of Phosphate Supplements. Management: This applies only to oral phosphate and iron administration. Administer oral phosphate supplements at least 1 hour before, or 2 hours after, oral iron salt administration. Exceptions: Sodium Glycerophosphate Pentahydrate. Consider therapy modification

Quinolone Antibiotics: Iron Salts may decrease the serum concentration of Quinolone Antibiotics. Management: Administer oral quinolones at least several hours before (4 h for moxi- and sparfloxacin, 2 h for others) or after (8 h for moxi-, 6 h for cipro-, 4 h for lome-, 3 h for gemi-, and 2 h for levo-, nor-, or ofloxacin or nalidixic acid) oral iron salts. Exceptions: LevoFLOXacin (Oral Inhalation). Consider therapy modification

Tetracycline Derivatives: May decrease the absorption of Iron Salts. Iron Salts may decrease the serum concentration of Tetracycline Derivatives. Consider therapy modification

Trientine: May decrease the serum concentration of Iron Salts. Iron Salts may decrease the serum concentration of Trientine. Management: Trientine manufacturer recommends avoiding concurrent use with oral iron salts due to the risk for impaired GI absorption of both trientine and the iron salt. Short courses of iron may be used; however, separate administration by at least 2 hours. Consider therapy modification

Adverse Reactions

Frequency not always defined.

Gastrointestinal: Diarrhea (21%), nausea (11%), constipation (8%), vomiting (7%), darkening of stools

Respiratory: Cough (6%)


Concerns related to adverse effects:

• Iron toxicity: May increase serum iron, ferritin, and transferrin saturation (TSAT), which may lead to excessive elevations in iron stores. Evaluate serum iron, ferritin, and TSAT at baseline and during therapy.

• Stool discoloration: May cause discolored (dark) stools related to iron content.

Disease-related concerns:

• Gastrointestinal diseases: Use with caution in patients with inflammatory bowel diseases or active, symptomatic GI bleeding because these patient populations were not included in clinical trials.

Concurrent drug therapy issues:

• Iron supplements: Patients receiving parenteral iron supplementation may require a dose reduction or discontinuation when ferric citrate is initiated.

• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

Other warnings/precautions:

• Overdose: Contains iron, a leading cause of fatal poisoning in children <6 years of age. Keep out of reach of children; in case of accidental overdose, immediately contact a poison control center or a health care provider.

Monitoring Parameters

Evaluate serum iron, ferritin, and transferrin saturation (TSAT) at baseline and during therapy. Periodically monitor serum phosphorus to assess therapy and adjust dosage if necessary.

Pregnancy Risk Factor


Pregnancy Considerations

Animal reproduction studies have not been conducted. Use of ferric citrate may increase iron stores, which may cause adverse events in pregnancy (fetal malformations, spontaneous abortion, and gestational diabetes noted with iron overdose in pregnant women).

Patient Education

• 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 cough or dark stools. Have patient report immediately to prescriber severe nausea, severe vomiting, severe diarrhea, 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.