Generic drug: paricalcitol

Brand name: Zemplar

What is Zemplar (paricalcitol), and how does it work?

Zemplar Capsules (paricalcitol) is a man-made form of vitamin D used to treat hyperparathyroidism (overactive parathyroid gland) in people with chronic kidney failure.

What are the side effects of Zemplar?

Many people using Zemplar do not have serious side effects. Tell your doctor if unlikely but serious side effects of Zemplar occur:

What is the dosage for Zemplar?

Chronic Kidney Disease Stages 3 And 4 In Adults

Administer Zemplar capsules orally once daily or three times a week. When dosing three times weekly, do not administer more frequently than every other day.

Initial Dose

Table 1. Recommended Zemplar Starting Dose Based upon Baseline iPTH Level

Baseline iPTH Level Daily Dose Three Times a Week Dose*
Less than or equal to 500 pg/mL 1 mcg 2 mcg
More than 500 pg/mL 2 mcg 4 mcg
* To be administered not more often than every other day
Dose Titration

Table 2. Recommended Zemplar Dose Titration Base upon iPTH Level

Dose Adjustment at 2 to 4 Week Intervals
iPTH Level Relative to Baseline Zemplar Capsule Dose Daily Dosage Three Times a Week Dosage*
The same, increased or decreased by less than 30% Increase dose by 1 mcg 2 mcg
Decreased by more than or equal to 30% and less than or equal to 60% Maintain dose - -
Decreased by more than 60% or iPTH less than 60 pg/mL Decrease dose by 1 mcg 2 mcg
* To be administered not more often than every other day

If a patient is taking the lowest dose, 1 mcg, on the daily regimen and a dose reduction is needed, the dose can be decreased to 1 mcg three times a week. If a further dose reduction is required, the drug should be withheld as needed and restarted at a lower dosing frequency.

Chronic Kidney Disease Stage 5 In Adults

Initial Dose

Administer the dose of Zemplar capsules orally three times a week, no more frequently than every other day based upon the following formula:

  • Dose (micrograms) = baseline iPTH (pg/mL) divided by 80

Treat patients only after their baseline serum calcium has been adjusted to 9.5 mg/dL or lower to minimize the risk of hypercalcemia.

Dose Titration

Individualize the dose of Zemplar based on iPTH, serum calcium and phosphorus levels. Titrate Zemplar dose based on the following formula:

  • Dose (micrograms) = most recent iPTH level (pg/ml) divided by 80

If serum calcium is elevated, the dose should be decreased by 2 to 4 micrograms.

As iPTH approaches the target range, small, individualized dose adjustments may be necessary in order to achieve a stable iPTH. In situations where monitoring of iPTH, Ca or P occurs less frequently than once per week, a more modest initial and dose titration ratio (e.g., iPTH divided by 100) may be warranted.

Pediatric Patients (Ages 10 To 16 Years)

CKD Stages 3 And 4

Initial Dose

  • Administer Zemplar 1 mcg capsule orally three times a week, no more frequently than every other day.

Dose Titration

  • Individualize and titrate Zemplar dose based on iPTH, serum calcium and phosphorus levels to maintain an iPTH level within target range.
  • Every 4 weeks, each administered Zemplar dose may be increased in 1 mcg increments, maintaining the three times per week regimen (e.g., increase from 1 mcg three times per week to 2 mcg three times per week).
  • At any time, each administered dose may be decreased by 1 mcg. Zemplar may be stopped if the patient requires reduction while receiving 1 mcg three times per week, resuming when appropriate.
CKD Stage 5

Initial Dose

Administer the dose of Zemplar capsules orally three times a week, no more frequently than every other day based upon the following formula:

  • Dose* (micrograms) = baseline iPTH (pg/mL) divided by 120

* Round down to the nearest whole number

Dose Titration

  • Subsequent dosing should be individualized and based on iPTH, serum calcium and phosphorus levels to maintain an iPTH level within target range.
  • Every 4 weeks, each administered Zemplar dose may be increased in 1 mcg increments, maintaining the three times per week regimen (e.g., increase from 1 mcg three times per week to 2 mcg three times per week).
  • At any time, each administered dose may be decreased by 2 mcg. Zemplar may be stopped if the patient requires reduction while receiving 2 mcg three times per week or 1 mcg three times per week, resuming when appropriate.

Monitoring

  • Monitor serum calcium and phosphorus levels closely after initiation of Zemplar, during dose titration periods and during co-administration with strong CYP3A inhibitors.
  • If hypercalcemia is observed, the dose of Zemplar should be reduced or withheld until these parameters are normalized.

Administration

  • Zemplar capsules may be taken without regard to food.

SLIDESHOW

Kidney Stones: Symptoms, Causes, and Treatment See Slideshow

What drugs interact with Zemplar?

Table 6 shows the clinically significant drug interactions with Zemplar capsules.

Table 6: Clinically Significant Drug Interactions with Paricalcitol

CYP3A Inhibitors
Clinical Impact Paricalcitol is partially metabolized by CYP3A. Hence, exposure of paricalcitol will increase upon coadministration with strong CYP3A inhibitors such as but not limited to: boceprevir, clarithromycin, conivaptan, grapefruit juice, indinavir, itraconazole, ketoconazole, lopinavir/ritonavir, mibefradil, nefazodone, nelfinavir, posaconazole, ritonavir, saquinavir, telaprevir, telithromycin, voriconazole.
Intervention Dose adjustment of Zemplar capsules may be necessary. Monitor closely for iPTH and serum calcium concentrations, if a patient initiates or discontinues therapy with a strong CYP3A4 inhibitor.
Cholestyramine
Clinical Impact Drugs that impair intestinal absorption of fat-soluble vitamins, such as cholestyramine, may interfere with the absorption of paricalcitol.
Intervention Recommend to take Zemplar capsules at least 1 hour before or 4 to 6 hours after taking cholestyramine (or at as great an interval as possible) to avoid impeding absorption of paricalcitol.
Mineral Oil
Clinical Impact Mineral oil or other substances that may affect absorption of fat may influence the absorption of paricalcitol.
Intervention Recommend to take Zemplar capsules at least 1 hour before or 4 to 6 hours after taking mineral oil (or at as great an interval as possible) to avoid affecting absorption of paricalcitol.

Is Zemplar safe to use while pregnant or breastfeeding?

  • Limited data with Zemplar capsules in pregnant women are insufficient to inform a drug-associated risk for major birth defects and miscarriage.
  • There are risks to the mother and fetus associated with chronic kidney disease in pregnancy.
  • There is no information available on the presence of paricalcitol in human milk, the effects of the drug on the breastfed infant or the effects of the drug on milk production.
  • Because of the potential for serious adverse reactions, including hypercalcemia in a breastfed infant, breastfeeding is not recommended during treatment with Zemplar.

QUESTION

The only purpose of the kidneys is to filter blood. See Answer

Summary

Zemplar Capsules (paricalcitol) is a man-made form of vitamin D used to treat hyperparathyroidism (overactive parathyroid gland) in people with chronic kidney failure. Side effects of Zemplar Capsules include fast/slow/irregular heartbeat, seizures, weakness, loss of appetite, back/bone/joint/muscle pain, constipation, diarrhea, dry mouth, eye pain or redness, eye sensitivity to light, headache, nausea/vomiting, drowsiness, stomach or abdominal pain, and others.

Treatment & Diagnosis

Medications & Supplements

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Medically Reviewed on 4/2/2021
References
All sections courtesy of the U.S. Food and Drug Administration