Ferric Citrate (oral)

Overview

Ferric Citrate, commonly marketed under the name Auryxia, is a prescription medication that is used primarily as a means of controlling levels of serum phosphorus in patients who are suffering from chronic kidney disease (CKD). It is used for such patients during a period of time when they are being treated with kidney dialysis but also has some utility when used to treat iron deficiency in patients who are not on dialysis yet still suffering from an iron deficiency as a result of their kidney problems. As a ferric iron-based phosphate binder this medication works by binding itself to phosphates in the bloodstream and aiding their passage through the digestive system. The goal is for the body to evacuate excess phosphates through the stool and thus maintain acceptable levels of phosphate in the bloodstream. When used correctly, Ferric Citrate can help the body begin to replenish a significant enough amount of iron to make a healthy amount of red blood cells.

This medication is typically taken on a very strict schedule and must be taken with meals, so successful use of this medication may require some changes to a patient's schedule or lifestyle that can be challenging when they are on a schedule for dialysis. When used to its fullest potential it has the ability to prevent many of the complications and debilitating health problems that are associated with high levels of phosphate in the blood as a result of kidney failure.

Conditions Treated

Type Of Medicine

  • Ferric iron-based phosphate binder

Side Effects

Ferric Citrate may cause some unwanted side effects in certain situations. While these side effects are not guaranteed to occur, patients who are going to take it as a course of treatment during dialysis should be aware of them and the way that they may complicate the therapy. Some of these side effects can be quite serious and require medical attention.

The most common side effect is an allergic reaction to the medication although there are others that are associated with an overdose of the medication. Some of the more common side effects, however, are considered temporary and usually subside as the body adjusts to the medication.

Some of these more common side effects include flu-like symptoms including coughing, vomiting, and nausea. Other patients complain of gastrointestinal problems such as diarrhea, constipation, or dark colored stools. While these routine side effects may not necessarily require medical attention, if they are making regular doses of the medicine difficult or are lasting longer than expected the patient should seek advice from their doctor. If the patient experiences other side effects that are not listed in the medical guide then the symptoms may indicate a more serious medical problem.

Dosage

When taking Ferric Citrate care must be taken with the dosage as it can cause serious health problems or an increased chance of side effects when used incorrectly. It should not be taken more often than directed or for a longer period of time than indicated in the prescription. All doses of the medication should be taken at mealtime with enough food to prevent digestive problems.

If the medication doxycycline is taken for the treatment of a bacterial infection it is only safe to use at least a full hour before taking the dose of ferric citrate. The dose of ferric citrate prescribed may vary from the recommendations from the manufacturer. The patient should use the dose that is indicated in the prescription as it may take into account a number of factors that the average dose does not.

When taking ferric citrate tablets for the control of phosphorus levels during dialysis, the dose will be two tablets three times per day at mealtimes. This may be adjusted upward if needed, but should not exceed 12 tablets in a single day. While this medication is usually only prescribed for adults, if it is used to treat Anemia in a child it must only be used as directed by a pediatric specialist. If a dose is missed it should be taken as soon as possible, but if it is more than a few hours it may be too close to the next dose to take safely. It is more dangerous to double dose this medication than to miss a dose, so skipping to the next dose may be the safest course of action.

Interactions

As with many medications, there is a certain risk of drug interactions when using ferric citrate with other pharmaceuticals. Using these medications together is usually not recommended but depending on the state of the patient's health it may be the best way to treat their condition. If a patient is taking Dimercaprol or Eltrombopag they should confer with their doctor to see if there are any precautions that can be taken including changing doses or prescriptions.

Use of ferric citrate carries a certain risk of side effects, but when mixed with certain drugs the risk of side effects from one or both prescriptions can be increased. Patients should make sure that their doctor knows if they are taking any of the following medications as there is an increased risk of side effects:

  • Carbidopa
  • Cefdinir
  • Demeclocycline
  • Dolutegravir
  • Doxycycline
  • Gatifloxacin
  • Grepafloxacin
  • Levodopa
  • Levofloxacin
  • Levothyroxine
  • Lomefloxacin
  • Methyldopa
  • Minocycline
  • Moxifloxacin
  • Mycophenolic Acid
  • Norfloxacin
  • Ofloxacin
  • Omeprazole
  • Penicillamine
  • Temafloxacin
  • Tetracycline
  • Trovafloxacin Mesylate
  • Zinc

While this is not an all-inclusive list it does include the most notable examples. Patients should clear any additional prescription or non-prescription medication with their doctor before taking them at the same time as ferric citrate. In addition, the medication can have adverse reactions to certain foods including dairy foods and food that contains phytic acid. A list of such foods should be provided at the time of prescription so that the patient knows what to avoid.

Certain medical conditions can affect the treatment of a patient with ferric citrate and the medication may make certain conditions worse. Patients that have Hemochromatosis and experience elevated iron levels should not take this medication as it can lead to a fatal iron overdose. Patients with inflammatory bowel disease or any gastrointestinal problems including bleeding may be able to take ferric citrate safely but must be closely monitored while taking the medication.

Warnings

Certain patients may have a predisposition that will prevent them from taking ferric citrate. The most common of these is an allergic reaction that can severely complicate treatment. This medication should not be used by patients suffering from elevated iron levels or hemochromatosis. This medication may not be safe to take for patients with a history of liver disease, severe stomach or gastrointestinal problems, or ulcers. Any surgery that has been performed on the gastrointestinal tract or abdomen should be closely scrutinized before prescribing ferric citrate.

Before deciding whether or not to use this medication during dialysis treatment an analysis of the good it will do versus the potential for harm should be undertaken. Any allergic reactions in the past may indicate that there is a potential for an allergic reaction to this medication. As this medication is rarely used for children, pregnant women, or the elderly there are insufficient studies about how the medication effects these vulnerable groups. However, since there is a significant danger of iron overdose from this medication such a regimen should only be prescribed with a great amount of caution. If a woman is breastfeeding while taking this medication she should be apprised of potential risks to the health of the infant before proceeding.

This medication changes the blood chemistry of the patient in a profound way and needs to be carefully monitored. Regular doctor visits will be necessary to perform blood tests to ensure that the medication is working as intended and that there are no unwanted effects as a result of taking ferric citrate. If there are any persistent gastrointestinal problems such as vomiting, diarrhea, or constipation while using this medication it may be cause for the physician to cease treatment with this drug.

While dark-colored stools may be a common side effect of this drug that is caused by iron in the bloodstream, it should be carefully monitored to ensure that it is not a symptom of a more serious condition. As this medication is known to elevate iron levels, additional caution should be taken with any vitamins or supplements that are taken as large amounts of iron are normally found in multivitamins. Any vitamins or herbal supplements that are taken while using ferric citrate should be cleared by the prescribing physician.

Storage

As with all medications, great care should be taken in the storage of ferric citrate tablets. It is especially important that this medication is stored in such a way that it is inaccessible to children as there is a significant risk of a fatal accidental overdose if this is taken by a child.

Take care to store this medication in its original container or another approved container with a child-resistant closure and store it in a place that is away from direct sunlight, heat, moisture, or freezing temperatures. This medication does not need to be refrigerated and doing so may lessen the effectiveness of its active ingredients. When this medication is no longer needed or has expired it should be disposed of in accordance with guidelines on the disposal of medical waste in the local area.

Summary

While ferric citrate is a very effective drug for treating an excess of phosphate in the bloodstream, it is a treatment option that must be taken with caution. While it has relatively few potential side effects, these side effects can affect the quality of the treatment. When used properly and without side effects, ferric citrate can have a significant impact on the health of patients who are undergoing dialysis treatment for their chronic kidney disease.