Paricalcitol

Generic Details

Generic Name

Paricalcitol

Other Names

  • Zemplar

Drug Class

  • Vitamin D Analogue

Chemical Formula

C27H44O3

Molecular Weight

416.63 g/mol

Mechanism of Action

  • Activates Vitamin D receptor, regulates calcium and phosphorus metabolism

Indications

  • Secondary hyperparathyroidism in chronic kidney disease
  • Hypercalcemia in patients with primary hyperparathyroidism

Common Dosage Forms

  • Capsule
  • Injection

Typical Dosage

  • Oral: 1-2 mcg/day
  • Intravenous: 5-10 mcg three times a week

Pediatric Dosage

  • Not established

Geriatric Dosage

  • Dose adjustment may be needed based on renal function

Side Effects

  • Hypercalcemia
  • Hypocalcemia
  • Headache
  • Nausea
  • Vomiting
  • Weakness

Contraindications

  • Hypercalcemia
  • Vitamin D toxicity

Pregnancy Category

  • C - Risk cannot be ruled out

Lactation Safety

  • Not known if excreted in breast milk, caution advised

Drug Interactions

  • Thiazide diuretics
  • Digoxin
  • Phenobarbital

Overdose Symptoms

  • Severe hypercalcemia

Antidote for Overdose

  • Discontinue paricalcitol, administer fluids, loop diuretics, and corticosteroids if necessary

Storage Conditions

  • Store at room temperature away from light and moisture

Pharmacokinetics

  • Absorption: Well absorbed orally
  • Distribution: Mainly bound to serum proteins
  • Metabolism: Hepatic
  • Excretion: Primarily fecal

Precautions

  • Monitor serum calcium and phosphorus levels regularly

Warnings

  • Risk of hypercalcemia, hypocalcemia, and vitamin D toxicity

Others

  • Avoid in patients with high levels of vitamin D