Usage
Sucroferric oxyhydroxide is prescribed for the control of serum phosphorus levels in patients with chronic kidney disease (CKD) on dialysis (hemodialysis or peritoneal dialysis). It is also indicated for the control of serum phosphorus levels in pediatric patients 2 years of age and older with CKD stages 4-5 (defined by a glomerular filtration rate <30 mL/min/1.73 m²) or with CKD on dialysis.
It is classified as a phosphate binder.
Sucroferric oxyhydroxide works by binding to dietary phosphate in the gastrointestinal tract. This prevents the phosphate from being absorbed into the bloodstream, thereby reducing serum phosphorus levels.
Alternate Names
The International Nonproprietary Name (INN) is iron. A commonly known brand name is Velphoro.
How It Works
Pharmacodynamics: Sucroferric oxyhydroxide lowers serum phosphate levels by binding to phosphate in the gut, forming an insoluble complex that is excreted in the feces. This reduces the absorption of phosphate from food.
Pharmacokinetics: Sucroferric oxyhydroxide is minimally absorbed systemically. The small amount of iron that may be released from the compound is absorbed and handled like dietary iron. The primary route of elimination for the phosphate-bound sucroferric oxyhydroxide complex is fecal excretion. A minimal amount of iron may be absorbed, which is then regulated by the body’s iron homeostasis mechanisms.
Mode of Action: Sucroferric oxyhydroxide acts locally in the gastrointestinal tract, where it binds to dietary phosphate. This interaction does not involve receptor binding, enzyme inhibition, or neurotransmitter modulation.
Elimination Pathways: The primary route of elimination for the sucroferric oxyhydroxide-phosphate complex is via fecal excretion.
Dosage
Standard Dosage
Adults:
Initial: 1500 mg of iron (equivalent to 3 tablets of Velphoro 500 mg) daily, administered with meals in three divided doses (one tablet with each meal).
Maintenance: Titrate dose in increments or decrements of 500 mg (one tablet) daily at intervals of one to four weeks as needed until an acceptable serum phosphorus level (≤5.5 mg/dL) is reached. Monitor serum phosphorus regularly and adjust dose accordingly.
Children (2 to <12 years of age):
Sucroferric oxyhydroxide is available as an oral powder in 125 mg sachets for pediatric use. The choice of formulation (powder or chewable tablets) depends on the patient’s age, preference, and ability to comply with treatment.
- 2 to <6 years: Starting dose 500 mg daily, titrated in increments of 125 mg or 250 mg; maximum daily dose 1250 mg.
- 6 to <9 years: Starting dose 750 mg daily, titrated in increments of 125 mg, 250 mg, or 375 mg; maximum daily dose 2500 mg.
- 9 to <12 years: Starting dose 1000 mg daily, titrated in increments of 250 mg or 500 mg; maximum daily dose 3000 mg.
Special Cases:
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Elderly Patients: No specific dose adjustment is necessary, but monitor renal function and serum phosphorus levels.
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Patients with Renal Impairment: Sucroferric oxyhydroxide is indicated for patients on dialysis. No clinical data is available for patients with earlier stages of renal impairment.
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Patients with Hepatic Dysfunction: Use with caution in patients with severe hepatic impairment.
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Patients with Comorbid Conditions: Use with caution in patients with peritonitis, significant gastrointestinal disorders, or major gastrointestinal surgery.
Clinical Use Cases
Sucroferric oxyhydroxide’s clinical use is specifically indicated for the control of hyperphosphatemia in patients with chronic kidney disease who are on dialysis. The dosing recommendations in this context are the same as the standard dosing outlined above. Intubation, surgical procedures, mechanical ventilation, ICU use, and emergency situations do not necessitate different dosing protocols for sucroferric oxyhydroxide.
Dosage Adjustments
Dosage adjustments are made based on serum phosphorus levels and should be titrated as described above.
Side Effects
Common Side Effects
Discolored (dark/black) feces, diarrhea, nausea.
Rare but Serious Side Effects
Allergic reactions (rash, itching, swelling), severe gastrointestinal issues (bleeding, abdominal pain).
Long-Term Effects
Potential for iron overload with prolonged use, although systemic absorption is minimal. Tooth discoloration can also occur.
Adverse Drug Reactions (ADR)
Severe allergic reactions.
Contraindications
Hemochromatosis and other iron accumulation disorders.
Drug Interactions
Sucroferric oxyhydroxide may decrease the absorption of certain medications, such as doxycycline, levothyroxine, ciprofloxacin, and some medications for osteoporosis or seizures. Administer these medications at least 1 hour before or 4 hours after sucroferric oxyhydroxide.
Pregnancy and Breastfeeding
Pregnancy Category B. Due to minimal systemic absorption, maternal use is not expected to result in fetal exposure. While excretion into breast milk is minimal, caution is advised.
Drug Profile Summary
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Mechanism of Action: Phosphate binder.
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Side Effects: Discolored feces, diarrhea, nausea.
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Contraindications: Hemochromatosis, iron overload.
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Drug Interactions: May reduce absorption of some drugs (e.g., doxycycline, levothyroxine).
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Pregnancy & Breastfeeding: Category B; use with caution.
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Dosage: Adults: 1500 mg daily initially, adjust based on serum phosphorus levels; Pediatric: Refer to pediatric dosage guidelines.
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Monitoring Parameters: Serum phosphorus, calcium, and parathyroid hormone (PTH) levels.
Popular Combinations
Often used in conjunction with calcium-based phosphate binders and/or vitamin D analogs or calcimimetics to control renal bone disease.
Precautions
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General Precautions: Monitor for gastrointestinal intolerance, iron overload, and tooth discoloration.
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Specific Populations: Use cautiously in those with peritonitis, significant gastric or hepatic disorders, or after major gastrointestinal surgery.
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Lifestyle Considerations: None specified.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Sucroferric oxyhydroxide?
A: Adults: Initially 1500 mg daily (three 500 mg tablets with meals), titrated to achieve optimal serum phosphorus control. For pediatric dosing, refer to pediatric guidelines.
Q2: How should Sucroferric oxyhydroxide be administered?
A: Chew or crush the tablets completely; do not swallow whole. Administer with meals.
Q3: What is the mechanism of action of Sucroferric oxyhydroxide?
A: It binds dietary phosphate in the gut, reducing its absorption and lowering serum phosphorus levels.
Q4: What are the common side effects of Sucroferric oxyhydroxide?
A: Discolored feces (black), diarrhea, and nausea.
Q5: Are there any contraindications to using Sucroferric oxyhydroxide?
A: Yes, it is contraindicated in patients with hemochromatosis or other iron overload disorders.
Q6: Does Sucroferric oxyhydroxide interact with other medications?
A: It can reduce the absorption of certain medications like doxycycline, levothyroxine, and others. These medications should be taken at different times.
Q7: Can Sucroferric oxyhydroxide be used in pregnant or breastfeeding women?
A: It is Pregnancy Category B. Use with caution after a careful risk/benefit assessment.
Q8: What monitoring parameters are important for patients taking Sucroferric oxyhydroxide?
A: Monitor serum phosphorus, calcium, and PTH levels regularly.
Q9: Are there any special considerations for elderly patients?
A: No specific dose adjustments are required, but monitor renal function and serum phosphorus closely.
Q10: What should patients do if they miss a dose?
A: Resume the normal dose with the next meal. Do not double the dose.
