Sevelamer
Sevelamer is a non-calcium, non-aluminum **phosphorus binding agent** used primarily in the management of hyperphosphatemia associated with **chronic kidney disease (CKD)**. * **Clinical Advantage**: Unlike traditional phosphate binders (such as aluminum hydroxide or calcium carbonate), sevelamer does not carry the risk of aluminum toxicity or iatrogenic hypercalcemia. * It is particularly useful in late-stage CKD patients who cannot tolerate aluminum salts or when calcium-based binders might exacerbate metastatic tissue calcification. * **Note**: It is generally more expensive than traditional aluminum or calcium-based products.
Mecanismo: Sevelamer is a cross-linked polymeric amine that acts locally in the gastrointestinal tract. * **Mechanism**: The polymer contains multiple amine groups that become partially protonated in the acidic environment of the stomach and intestine. These protonated amines interact with dietary phosphate ions via **ionic and hydrogen bonding** → preventing phosphate absorption across the gut wall → increasing fecal excretion of phosphate → ultimately lowering serum phosphorus levels. * **Secondary Effects**: It also binds bile acids in the gut, which can lead to a reduction in serum low-density lipoproteins (LDL) and total cholesterol.
Dosificación por especie
- Hyperphosphatemia · 200 mg 2-3 times daily · PO · q8-12h · Anecdotally appears to be safe and effective.
- Chronic kidney disease (hyperphosphataemia) · 30-40 mg/kg · PO · q8h · Titrated to the desired serum phosphate concentration · Should be given with meals and at least 1 hour before or 3 hours after other medications.
- Hyperphosphatemia · 400 mg PO with meals · PO · with meals · For medium to large sized dog
- Chronic kidney disease (hyperphosphataemia) · 30-40 mg/kg · PO · q8h · Titrated to the desired serum phosphate concentration · Should be given with meals and at least 1 hour before or 3 hours after other medications.
Las dosis son una referencia clínica para médicos veterinarios. Confirme siempre con la información vigente del producto y el paciente individual.
Vías de administración
Contraindicaciones
- Hypophosphatemia
- Bowel obstruction
- Known hypersensitivity to sevelamer
- Gastrointestinal obstruction
Efectos adversos
- Gastrointestinal upset (nausea, vomiting, diarrhea, or constipation)
- Decreased absorption of fat-soluble vitamins (A, D, E, K) and folic acid
- Constipation
- Pills are hygroscopic and will expand (potential risk of esophageal obstruction if not swallowed quickly)
Interacciones farmacológicas
- Anticonvulsants (oral) · Sevelamer may reduce oral absorption; give at least 1 hour before or 3 hours after sevelamer.
- Antiarrhythmics (oral) · Sevelamer may reduce oral absorption; give at least 1 hour before or 3 hours after sevelamer.
- Ciprofloxacin (and other oral fluoroquinolones) · Concurrent administration may decrease absorption by 50%; administer at least 1 hour before or 3 hours after sevelamer.
- Oral Medications (Narrow Therapeutic Index) · May reduce absorption; consider dosing other oral drugs separately.
- Vitamins · Sevelamer may reduce vitamin absorption from food; consider administering vitamin supplements separately.
- Other oral medications · May bind to and decrease the absorption of concurrently administered oral drugs. Should be given at least 1 hour before or 3 hours after other medications. · moderate
- Fat-soluble vitamins (e.g., Vitamin K) · May inhibit vitamin absorption; consider monitoring prothrombin time. · moderate
Monitoreo
- Serum phosphorus
- Serum calcium
- Serum bicarbonate
- Serum chloride
- Baseline coagulation screening test (before and after therapy implementation, due to potential Vitamin K malabsorption)
- Serum phosphate levels (at 4-6 week intervals to adjust dosage)
- Prothrombin time (due to potential vitamin K malabsorption)
- Bowel movements (monitor for constipation)
Sobredosis
Because sevelamer is not absorbed systemically, the potential for acute toxicity from an overdose appears to be **negligible**. Overdose would likely result in gastrointestinal distress (constipation or diarrhea) and potential hypophosphatemia.
La referencia de fármacos de VetSheet está destinada a médicos veterinarios como apoyo a la decisión clínica; no sustituye el juicio profesional ni la información vigente del fabricante.