Brand names: Renagel, Renvela
Drug class: Phosphate-reducing Agents

Medically reviewed by Drugs.com on Apr 10, 2024. Written by ASHP.

Introduction

Phosphate binder used to reduce the intestinal absorption of phosphates;^{1 2 3 4 5 6 7 8 22 23} allylamine polymer (cross-linked with epichlorohydrin).^{1 2 3 4 5 6 7 8 22}

Uses for Sevelamer (Local)

Hyperphosphatemia

Reduction of serum phosphorus in patients with chronic kidney disease (CKD) who are undergoing dialysis.^{1 2 3 4 6 23}

Risk of hypercalcemia is less than with calcium salts.²

Safety and efficacy not established in patients with CKD who are not undergoing dialysis.^{1 23}

Sevelamer (Local) Dosage and Administration

Administration

Oral Administration

Administer orally 3 times daily with meals.^{1 23}

Dosage

Available as sevelamer carbonate and sevelamer hydrochloride; dosage expressed in terms of the salts.^{1 23} Sevelamer carbonate dosage expected to be similar to that of sevelamer hydrochloride because of rapid disintegration of sevelamer carbonate tablets in gastric hydrochloric acid.²³

Adults

Hyperphosphatemia in CKD Patients Undergoing Dialysis

Sevelamer Carbonate

Initial dosage in patients not currently receiving a phosphate binder (e.g., calcium acetate) depends on serum phosphorus concentrations.²³

Initial dosage in patients being transferred to sevelamer from calcium acetate therapy depends on current calcium acetate dosage.²³

For the treatment of hyperphosphatemia in patients currently receiving sevelamer hydrochloride therapy, the recommended initial dosage of sevelamer carbonate is equivalent to the patient's current sevelamer hydrochloride dosage on a gram per gram basis.²³

Adjust dosage of sevelamer carbonate for all patients according to the patient’s serum phosphorus concentrations with the goal of controlling serum phosphorus concentrations within the target range of 3.5–5.5 mg/dL.²³ Increase or decrease dosage in increments of 1 tablet (800 mg) per meal at 2-week intervals as needed.²³

Average dosage of sevelamer carbonate in one study was 6 g daily; maximum dosage studied was 14 g daily.²³

Sevelamer Hydrochloride

Initial dosage in patients not currently receiving a phosphate binder (e.g., calcium acetate) depends on serum phosphorus concentrations.¹

Initial dosage in patients being transferred to sevelamer from calcium acetate therapy depends on current calcium acetate dosage.¹

Adjust dosage of sevelamer hydrochloride for all patients according to serum phosphorus concentrations with the goal of reducing concentrations to ≤5.5 mg/dL.¹ Increase or decrease dosage in increments of 1 tablet (400 or 800 mg) per meal at 2-week intervals as needed.^{1 7 22}

Average dosage of sevelamer hydrochloride in one study was 2.4 g per meal (7.2 g daily); maximum average dosage studied was 13 g daily.¹

Special Populations

Geriatric Patients

Select dosage cautiously, usually initiating therapy at the low end of the dosage range.^{1 23}

Cautions for Sevelamer (Local)

Contraindications

• Hypophosphatemia.^{1 23}

• Bowel obstruction.^{1 23}

Warnings/Precautions

General Precautions

GI Disease or Surgery

Use with caution in patients with swallowing or severe GI motility disorders (including severe constipation), dysphagia, or major GI tract surgery.^{1 23} Provide appropriate treatment to patients who develop constipation or experience worsening of existing constipation to avoid the development of severe complications (e.g., fecal impaction, ileus, intestinal obstruction, intestinal perforation).^{1 23}

Monitor patients on peritoneal dialysis for proper use of aseptic technique and for signs and symptoms of peritonitis.^{1 23}

Effects on Vitamins

Sevelamer hydrochloride has decreased plasma concentrations of vitamins D, E, and K and folic acid in animals when given at doses 6–10 times the recommended human dosage.¹ No evidence of decreased vitamin concentrations in some short-term studies of patients receiving sevelamer hydrochloride;^{1 2 5 23} however, a decrease in serum 25-hydroxy vitamin D₃ concentrations from 39 to 34 mcg/mL (normal range: 10–55 mcg/mL) was reported in one 1-year study.¹ Most patients (75%) in clinical studies of sevelamer hydrochloride have received vitamin supplements.^{1 23} Monitor for reduced serum concentrations of vitamin D, E, K (clotting factors) and folic acid.¹

Adequate Patient Monitoring

Monitor serum chloride and bicarbonate concentrations.^{1 22 23}

Specific Populations

Pregnancy

Category C.^{1 23}

Requirements for vitamins and other nutrients are increased during pregnancy; the effect of sevelamer on vitamin and other nutrient absorption has not been studied in pregnant women.^{1 23}

Lactation

Caution is advised if used in nursing women.²²

Pediatric Use

Safety and efficacy not established in children <18 years of age.^{1 2 3 4 22 23}

Geriatric Use

Insufficient experience in patients ≥65 years of age to determine whether geriatric patients respond differently than younger adults; select dosage with caution.^{1 23} (See Geriatric Patients under Dosage and Administration.)

Common Adverse Effects

Abdominal pain,^{1 23} constipation,^{1 23} diarrhea,^{1 2 3 4 23} dyspepsia,^{1 3 4 5 23} flatulence,^{1 23} nausea,^{1 2 3 4 23} peritonitis (in patients on peritoneal dialysis),^{1 23} vomiting.^{1 2 3 23}

Drug Interactions

Effects on GI Absorption of Drugs

Possible decreased bioavailability of orally administered drugs given concomitantly; when reduced bioavailability would have a clinically important effect on the drug's safety or efficacy, administer the drug ≥1 hour before or 3 hours after sevelamer administration or consider monitoring blood concentrations.^{1 23}

Specific Drugs

No drug interaction studies have been performed with sevelamer carbonate.²³ Drug interactions studies have been performed with sevelamer hydrochloride in humans.²³

Sevelamer (Local) Pharmacokinetics

Absorption

Not systemically absorbed following oral administration in healthy individuals;^{1 3 4 5 6 7 8 23} no absorption studies to date in patients with renal disease.^{1 23}

Elimination

Elimination Route

Excreted in the feces as unabsorbed drug bound to phosphate ions^{2 3 4 5 8} and to bile acids.^{2 22}

Stability

Storage

Oral

Tablets

25°C (may be exposed to 15–30°C).^{1 23} Protect from moisture.^{1 23}

Actions

• Following oral administration, binds phosphate ions through ionic and hydrogen bonding.^{1 2 3 4 5 23}

• Reduced phosphate absorption decreases serum and urinary phosphorus concentrations^{1 8 22 23} and increases fecal excretion of phosphorus.⁸

• No substantial changes in serum calcium concentrations reported.^{2 3 4 5 6}

• Binds bile acids in the intestine,^{1 2 23} forming a nonabsorbable complex.²²

• May interfere with normal fat absorption, possibly reducing absorption of fat-soluble vitamins (e.g., vitamin A, D, K).^{1 23}

• Decreases serum total and LDL-cholesterol concentrations;^{1 2 3 4 5 6 7 8 23} does not appear to alter serum HDL-cholesterol^{1 5 23} or triglyceride^{1 3 6 23} concentrations.

• Does not alter serum chloride,³ bicarbonate,³ or albumin concentrations.^{1 23}

• Does not contain aluminum or other metals; does not produce aluminum toxicity.^{4 5}

Advice to Patients

• Importance of adherence to instructions about diet.^{1 10 23}

• Importance of taking sevelamer with meals.^{1 23}

• Importance of advising patients to take certain other drugs (e.g., antiarrhythmic agents, anticonvulsants, ciprofloxacin) ≥1 hour before or 3 hours after taking sevelamer.^{1 23}

• Importance of advising patients of risk of severe complications from untreated constipation; importance of patients promptly reporting new onset or worsening of existing constipation to clinician.^{1 23}

• Importance of women informing their clinician if they are or plan to become pregnant or plan to breast-feed.^{1 23}

• Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs.^{1 23}

• Importance of informing patients of other important precautionary information. (See Cautions.)

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Medical Disclaimer