Sevelamer Dosing for Adults with Chronic Kidney Disease
Starting Dose
Start with 800 mg three times daily with meals (or alternatively 1600 mg three times daily with meals for two 800 mg tablets per meal), or 2-4 tablets of the 400 mg formulation three times daily with meals. 1
Dose Titration
- Adjust the dose by one tablet per meal at two-week intervals based on serum phosphorus levels to achieve target ranges 1
- The goal is to reach serum phosphorus of 3.5-5.5 mg/dL in dialysis patients (CKD Stage 5) 2, 3
- For non-dialysis CKD patients (Stages 3-4), target serum phosphorus of 2.7-4.6 mg/dL 3
Administration Guidelines
- Administer sevelamer 10-15 minutes before or during meals to maximize phosphate binding, as the medication must be taken with food to bind dietary phosphorus in the gastrointestinal tract 2
- Tablets should be swallowed whole per FDA labeling 1, though emerging evidence suggests crushing may be feasible for enteral tube administration in select cases 4
Dosing in Clinical Practice
- In the pivotal trial comparing sevelamer to calcium-based binders, patients achieved K/DOQI phosphorus targets with sevelamer, demonstrating effective phosphorus control 5
- Nine 800 mg tablets per day (three tablets three times daily with meals) of sevelamer monotherapy has been shown to achieve K/DOQI serum phosphorus and calcium-phosphorus product targets 6
- Once-daily dosing of sevelamer carbonate powder is less effective than thrice-daily tablet dosing and is not recommended as standard therapy 7
Specific Clinical Scenarios Favoring Sevelamer
Sevelamer is strongly preferred over calcium-based binders when:
- Serum calcium exceeds 10.2 mg/dL (hypercalcemia) 2, 3
- PTH levels are suppressed below 150 pg/mL on two consecutive measurements 3
- Patients already receive more than 2,000 mg/day of elemental calcium from calcium-based binders 5
- Severe vascular or coronary artery calcification is present 2, 3
- Calcium-phosphorus product exceeds 55 mg²/dL² 5, 3
Combination Therapy
- When hyperphosphatemia persists despite monotherapy, combine sevelamer with calcium-based binders while ensuring total elemental calcium intake (dietary plus binders) does not exceed 2,000 mg/day 3
- This approach allows phosphorus control while limiting calcium load and associated vascular calcification risk 5
Important Monitoring Parameters
- Monitor serum phosphorus levels every 2 weeks during dose titration 1
- Maintain calcium-phosphorus product below 55 mg²/dL² 5, 3
- Keep serum calcium in the normal range, preferably toward the lower end (8.4-9.5 mg/dL) 5, 3
Common Pitfalls to Avoid
- Do not administer sevelamer without food - it will be ineffective as it requires dietary phosphate to bind 2
- Separate sevelamer from ciprofloxacin and mycophenolate mofetil administration, as sevelamer binds these medications and reduces their absorption 1
- Be aware that gastrointestinal adverse effects (dyspepsia, nausea, constipation, diarrhea) are the most common reasons for discontinuation 1
- Serious complications including bowel obstruction, perforation, and bleeding gastrointestinal ulcers have been reported and may require hospitalization 1
Cardiovascular Benefits Beyond Phosphate Control
- Sevelamer provides additional cardiovascular benefits by reducing LDL cholesterol and preventing progression of coronary and aortic calcification compared to calcium-based binders 5, 2
- In patients with baseline vascular calcification, sevelamer prevented progression while calcium-based binders showed significant worsening 5