Drug Detail:Doxercalciferol (monograph) (Hectorol)
Drug Class:
Usual Adult Dose for Secondary Hyperparathyroidism
Intravenous dosing for patients on dialysis:
Initial dose:
- Intact parathyroid hormone (iPTH) over 400 pg/mL: 4 mcg IV 3 times per week at the end of dialysis, or approximately every other day
- iPTH decreased less than 50% AND above 300 pg/mL: increase 1 to 2 mcg every 8 weeks as needed
- iPTH decreased more than 50% AND above 300 pg/mL: maintain previous dose
- iPTH 150 to 300 pg/mL: maintain previous dose
- iPTH below 100 pg/mL: suspend dosing for 1 week, then resume at a dose at least 1 mcg lower
- Doses higher than 18 mcg weekly have not been studied
Oral dosing for patients on dialysis:
Initial dose:
- iPTH over 400 pg/mL: 10 mcg orally 3 times per week at the end of dialysis, or approximately every other day
- iPTH decreased less than 50% AND above 300 pg/mL: increase 2.5 mcg every 8 weeks as needed
- iPTH 150 to 300 pg/mL: maintain previous dose
- iPTH below 100 pg/mL: suspend dosing for 1 week, then resume at a dose at least 2.5 mcg lower
Oral dosing, pre-dialysis, Stage 3 or 4 Chronic Kidney Disease (CKD):
Initial dose:
- iPTH over 70 pg/mL (Stage 3 CKD): 1 mcg, orally, once a day
- iPTH over 110 pg/mL (Stage 4 CKD): 1 mcg, orally, once a day
- iPTH over 70 pg/mL (Stage 3 CKD): increase by 0.5 mcg at 2 week intervals, as needed
- iPTH over 110 pg/mL (Stage 4 CKD): increase by 0.5 mcg at 2 week intervals, as needed
- iPTH 35 to 70 pg/mL (Stage 3 CKD): maintain previous dose
- iPTH 70 to 110 pg/mL (Stage 4 CKD): maintain previous dose
- iPTH below 35 pg/mL (Stage 3 CKD): suspend dosing for 1 week, then resume at a dose at least 0.5 mcg lower
- iPTH below 70 pg/mL (Stage 4 CKD): suspend dosing for 1 week, then resume at a dose at least 0.5 mcg lower
Comments:
- Individualize dosing based on iPTH levels with monitoring of serum calcium and phosphorus.
- Reduce dose or suspend treatment for hypercalcemia, hyperphosphatemia, or a serum calcium times phosphorus product greater than 55 mg(2)/dL(2).
Uses: Treatment of secondary hyperparathyroidism in patients with chronic kidney disease on dialysis, or patients with Stage 3 or 4 chronic kidney disease.
Renal Dose Adjustments
See Usual Adult Dose
Data not available for Stage 2 chronic kidney disease
Liver Dose Adjustments
Use with caution.
- More frequent monitoring of intact parathyroid hormone (iPTH), calcium, and phosphorus levels is recommended.
Precautions
Safety and efficacy have not been established in patients younger than 18 years.
Consult WARNINGS section for additional precautions.
Dialysis
See Usual Adult Dose
Other Comments
Storage requirements:
- Store at controlled room temperature (77F).
Monitoring:
- Determine serum calcium, phosphorus, and iPTH prior to treatment.
- Weekly monitoring of serum calcium, phosphorus, and iPTH is recommended during treatment of dialysis patients.
- Every other week monitoring of serum calcium, phosphorus, and iPTH is recommended during treatment initiation and dose adjustments in pre-dialysis patients; monitor monthly for 3 months once stabilized, then every 3 months thereafter.
Patient advice:
- Advise patients and caregivers about adherence to diet, calcium supplementation, and avoidance of nonprescription drugs without physician approval.
- Inform patients of the symptoms of hypercalcemia.
