Paricalcitol 5mcg/ml Inj, 1ml
It is used to treat or prevent high parathyroid hormone levels in certain patients.
Drug Class
Vitamin D Analog
Pharmacologic Class
Selective Vitamin D Receptor Activator (VDRA)
Pregnancy Category
Category C
FDA Approved
Dec 1998
DEA Schedule
Not Controlled
Overview
What is this medicine?
Paricalcitol is a man-made form of vitamin D that helps control the levels of parathyroid hormone (PTH), calcium, and phosphorus in your body. It is used in people with severe kidney disease who are on dialysis to prevent or treat a condition called secondary hyperparathyroidism, where the parathyroid glands make too much PTH.
How to Use This Medicine
To use this medication correctly, follow your doctor's instructions and carefully read all accompanying information. Take this medication exactly as directed, and adhere to all guidelines provided. This drug is administered via intravenous injection.
For storage and disposal, consult with your doctor, nurse, or pharmacist to determine the best approach if you need to keep this medication at home.
If you miss a dose, contact your doctor promptly to receive guidance on the next steps to take.
For storage and disposal, consult with your doctor, nurse, or pharmacist to determine the best approach if you need to keep this medication at home.
If you miss a dose, contact your doctor promptly to receive guidance on the next steps to take.
Lifestyle & Tips
- Follow your doctor's instructions regarding diet, especially limiting phosphorus intake.
- Take any prescribed phosphate binders as directed, usually with meals.
- Do not take any other vitamin D supplements or calcium supplements unless specifically instructed by your doctor.
- Report any new medications, over-the-counter drugs, or herbal supplements to your doctor or pharmacist.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
Initial dose based on baseline PTH levels for CKD Stage 5 patients on hemodialysis or peritoneal dialysis. If baseline iPTH is < 500 pg/mL, initial dose is 0.04 mcg/kg administered as a bolus injection 3 times per week. If baseline iPTH is >= 500 pg/mL, initial dose is 0.08 mcg/kg administered as a bolus injection 3 times per week. Doses are adjusted based on serum iPTH, calcium, and phosphorus levels.
Dose Range:
0.04 - 0.24 mg
Condition-Specific Dosing:
CKD_Stage_5_Hemodialysis_Peritoneal_Dialysis:
Initial dose 0.04 mcg/kg or 0.08 mcg/kg 3 times per week, adjusted to maintain iPTH in target range (150-300 pg/mL) without causing hypercalcemia or hyperphosphatemia. Maximum dose studied is 0.24 mcg/kg 3 times per week.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established
Dose Adjustments
Renal Impairment:
Mild:
Not applicable (indicated for CKD Stage 5)
Moderate:
Not applicable (indicated for CKD Stage 5)
Severe:
Dosing is for patients with severe renal impairment (CKD Stage 5) requiring dialysis.
Dialysis:
Administered 3 times per week during dialysis sessions. Dosing is adjusted based on iPTH, calcium, and phosphorus levels.
Hepatic Impairment:
Mild:
No specific dose adjustment recommended.
Moderate:
No specific dose adjustment recommended.
Severe:
No specific dose adjustment recommended.
Pharmacology
Mechanism of Action
Paricalcitol is a synthetic analog of calcitriol, the active form of vitamin D. It selectively activates the vitamin D receptor (VDR) in the parathyroid glands, leading to a reduction in parathyroid hormone (PTH) synthesis and secretion. It has a relatively low impact on intestinal calcium and phosphorus absorption compared to calcitriol, which helps to minimize the risk of hypercalcemia and hyperphosphatemia.
Pharmacokinetics
Absorption:
Bioavailability:
100%
Tmax:
Not applicable (IV administration)
FoodEffect:
Not applicable (IV administration)
Distribution:
Vd:
Approximately 0.6 L/kg
ProteinBinding:
Greater than 99%
CnssPenetration:
Limited
Elimination:
HalfLife:
Approximately 4-7 hours (terminal half-life)
Clearance:
Not precisely quantified, but primarily hepatic and biliary.
ExcretionRoute:
Primarily fecal (approximately 70%), with a smaller portion excreted renally (approximately 30%).
Unchanged:
Less than 2% of the administered dose is excreted unchanged in urine.
Pharmacodynamics
OnsetOfAction:
Within hours (PTH suppression)
PeakEffect:
Within days to weeks (stable PTH reduction)
DurationOfAction:
Several days (due to half-life and sustained PTH suppression)
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of high calcium levels, including:
+ Weakness
+ Confusion
+ Feeling tired
+ Headache
+ Upset stomach and vomiting
+ Constipation
+ Bone pain
Signs of high or low blood pressure, such as:
+ Severe headache or dizziness
+ Passing out
+ Changes in eyesight
Abnormal heartbeat
Seizures
Increased urination
Weight loss
Decreased appetite
Unusual thirst
Swelling
Vomiting blood or coffee ground-like material
Black, tarry, or bloody stools
Fever or chills
Other Possible Side Effects
Like all medications, this drug can cause side effects. Many people may not experience any side effects or only minor ones. If you notice any of the following side effects or any other unusual symptoms, contact your doctor for advice:
Diarrhea
Upset stomach or vomiting
Dizziness or headache
Nose or throat irritation
Trouble sleeping
Joint pain
Eye redness
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of high calcium levels, including:
+ Weakness
+ Confusion
+ Feeling tired
+ Headache
+ Upset stomach and vomiting
+ Constipation
+ Bone pain
Signs of high or low blood pressure, such as:
+ Severe headache or dizziness
+ Passing out
+ Changes in eyesight
Abnormal heartbeat
Seizures
Increased urination
Weight loss
Decreased appetite
Unusual thirst
Swelling
Vomiting blood or coffee ground-like material
Black, tarry, or bloody stools
Fever or chills
Other Possible Side Effects
Like all medications, this drug can cause side effects. Many people may not experience any side effects or only minor ones. If you notice any of the following side effects or any other unusual symptoms, contact your doctor for advice:
Diarrhea
Upset stomach or vomiting
Dizziness or headache
Nose or throat irritation
Trouble sleeping
Joint pain
Eye redness
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Signs of high calcium (hypercalcemia): feeling sick to your stomach (nausea), throwing up (vomiting), constipation, loss of appetite, feeling very tired or weak, confusion, increased thirst, increased urination, muscle aches.
- Signs of high phosphorus (hyperphosphatemia): itching, bone pain, red eyes.
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain health conditions, such as high calcium levels or high vitamin D levels, as these may affect your ability to take this medication safely.
If you are breastfeeding, as you should not breastfeed while taking this medication.
This medication may interact with other medications or health conditions. Therefore, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter medications you are taking
Any natural products or vitamins you are using
Your complete medical history, including any health problems you have
Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to ensure your safety. It is your responsibility to verify that it is safe to take this medication with all your other medications and health conditions.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain health conditions, such as high calcium levels or high vitamin D levels, as these may affect your ability to take this medication safely.
If you are breastfeeding, as you should not breastfeed while taking this medication.
This medication may interact with other medications or health conditions. Therefore, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter medications you are taking
Any natural products or vitamins you are using
Your complete medical history, including any health problems you have
Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to ensure your safety. It is your responsibility to verify that it is safe to take this medication with all your other medications and health conditions.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Regular blood tests will be necessary, as directed by your doctor, to monitor your condition. Be sure to discuss any concerns or questions with your doctor.
If you are currently taking other supplements that contain vitamin D, consult with your doctor to avoid excessive intake. Additionally, if you are using antacids or other products that contain aluminum, inform your doctor, as this may interact with your medication.
Grapefruit and grapefruit juice may also interact with this medication, so it is crucial to discuss your consumption of these with your doctor. To maximize the effectiveness of your treatment, follow the dietary plan recommended by your doctor.
If you are pregnant or planning to become pregnant, notify your doctor immediately. You and your doctor will need to carefully weigh the benefits and risks of using this medication during pregnancy to ensure the best possible outcome for you and your baby.
If you are currently taking other supplements that contain vitamin D, consult with your doctor to avoid excessive intake. Additionally, if you are using antacids or other products that contain aluminum, inform your doctor, as this may interact with your medication.
Grapefruit and grapefruit juice may also interact with this medication, so it is crucial to discuss your consumption of these with your doctor. To maximize the effectiveness of your treatment, follow the dietary plan recommended by your doctor.
If you are pregnant or planning to become pregnant, notify your doctor immediately. You and your doctor will need to carefully weigh the benefits and risks of using this medication during pregnancy to ensure the best possible outcome for you and your baby.
Overdose Information
Overdose Symptoms:
- Hypercalcemia (severe nausea, vomiting, anorexia, weakness, fatigue, confusion, polyuria, polydipsia, dehydration, stupor, coma, cardiac arrhythmias)
- Hyperphosphatemia
- Hypermagnesemia (if co-administered with magnesium-containing products)
What to Do:
Immediately contact your doctor or emergency services. Treatment involves discontinuing paricalcitol, monitoring serum calcium, phosphorus, and magnesium, and initiating measures to lower these levels (e.g., hydration, loop diuretics, corticosteroids, dialysis if severe).
Drug Interactions
Major Interactions
- CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin, itraconazole, ritonavir): May significantly increase paricalcitol exposure, increasing risk of hypercalcemia and hyperphosphatemia. Co-administration should be avoided or paricalcitol dose significantly reduced with close monitoring.
Moderate Interactions
- Phosphate binders (calcium-containing): Increased risk of hypercalcemia.
- Magnesium-containing antacids/laxatives: Increased risk of hypermagnesemia, especially in patients with renal impairment.
- Other vitamin D analogs or derivatives: Increased risk of hypercalcemia and hyperphosphatemia.
- Thiazide diuretics: May increase risk of hypercalcemia.
Monitoring
Baseline Monitoring
Serum Calcium
Rationale: To establish baseline and guide initial dosing, and to monitor for hypercalcemia.
Timing: Prior to initiation of therapy.
Serum Phosphorus
Rationale: To establish baseline and guide initial dosing, and to monitor for hyperphosphatemia.
Timing: Prior to initiation of therapy.
Intact Parathyroid Hormone (iPTH)
Rationale: To establish baseline and guide initial dosing, and to monitor therapeutic response.
Timing: Prior to initiation of therapy.
Serum Alkaline Phosphatase
Rationale: To assess bone turnover and mineral metabolism.
Timing: Prior to initiation of therapy.
Routine Monitoring
Serum Calcium
Frequency: At least weekly during dose titration, then monthly once stable.
Target: 8.4-10.2 mg/dL (or as per clinical guidelines for CKD patients)
Action Threshold: If corrected serum calcium exceeds 10.5 mg/dL, reduce or interrupt paricalcitol dose.
Serum Phosphorus
Frequency: At least weekly during dose titration, then monthly once stable.
Target: 2.5-4.5 mg/dL (or as per clinical guidelines for CKD patients)
Action Threshold: If serum phosphorus exceeds 5.5 mg/dL, reduce or interrupt paricalcitol dose and/or adjust phosphate binder therapy.
Intact Parathyroid Hormone (iPTH)
Frequency: Every 2-4 weeks during dose titration, then every 1-3 months once stable.
Target: 150-300 pg/mL (KDOQI guidelines for CKD Stage 5)
Action Threshold: Adjust dose if iPTH is consistently outside target range.
Symptom Monitoring
- Symptoms of hypercalcemia (e.g., nausea, vomiting, constipation, anorexia, weakness, fatigue, confusion, polyuria, polydipsia, muscle pain)
- Symptoms of hyperphosphatemia (e.g., pruritus, bone pain, vascular calcification symptoms)
Special Patient Groups
Pregnancy
Category C. There are no adequate and well-controlled studies in pregnant women. Use during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Trimester-Specific Risks:
First Trimester:
Potential risk to fetus, but human data is limited.
Second Trimester:
Potential risk to fetus, but human data is limited.
Third Trimester:
Potential risk to fetus, but human data is limited.
Lactation
It is not known whether paricalcitol is excreted in human milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions in nursing infants from paricalcitol, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
Infant Risk:
Unknown, but potential for hypercalcemia or other adverse effects in the infant. Monitor infant for signs of hypercalcemia.
Pediatric Use
Safety and efficacy have not been established in pediatric patients. Use is not recommended.
Geriatric Use
No overall differences in safety or effectiveness have been observed between elderly and younger patients. Dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.
Clinical Information
Clinical Pearls
- Paricalcitol is a selective VDR activator, meaning it aims to suppress PTH with less impact on calcium and phosphorus levels compared to non-selective vitamin D analogs like calcitriol.
- Close and frequent monitoring of serum calcium, phosphorus, and iPTH is crucial, especially during dose initiation and titration, to prevent hypercalcemia and hyperphosphatemia.
- Patients should be educated on the symptoms of hypercalcemia and instructed to report them immediately.
- Avoid concomitant use with CYP3A4 inhibitors due to increased risk of paricalcitol exposure and adverse effects.
- Ensure patients are adhering to their prescribed phosphate binder regimen and dietary phosphorus restrictions, as these are critical for managing mineral and bone disorder in CKD.
Alternative Therapies
- Calcitriol (Rocaltrol, Calcijex)
- Doxercalciferol (Hectorol)
- Cinacalcet (Sensipar) - a calcimimetic, not a vitamin D analog, but also used for secondary hyperparathyroidism.
Cost & Coverage
Average Cost:
Highly variable, typically several hundred to over a thousand USD per 1ml vial (5mcg/ml)
Generic Available:
Yes
Insurance Coverage:
Tier 3 or Specialty Tier (for brand), Tier 1 or 2 (for generic) - varies by insurance plan.
General Drug Facts
If your symptoms or health problems do not improve or worsen over time, it is essential to contact your doctor for further evaluation and guidance. To ensure safe and effective treatment, never share your medication with others or take someone else's medication.
Store all medications in a secure location, out of the reach of children and pets, to prevent accidental ingestion or exposure. Properly dispose of unused or expired medications by checking with your pharmacist for guidance on the best disposal method. Unless instructed to do so by a healthcare professional or pharmacist, avoid flushing medications down the toilet or pouring them down the drain. Many communities have drug take-back programs, which your pharmacist can help you locate.
Some medications may come with an additional patient information leaflet, so it is a good idea to check with your pharmacist for more information. If you have any questions or concerns about your medication, consult with your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. Be prepared to provide information about the medication taken, the amount, and the time it was taken to ensure prompt and effective treatment.
Store all medications in a secure location, out of the reach of children and pets, to prevent accidental ingestion or exposure. Properly dispose of unused or expired medications by checking with your pharmacist for guidance on the best disposal method. Unless instructed to do so by a healthcare professional or pharmacist, avoid flushing medications down the toilet or pouring them down the drain. Many communities have drug take-back programs, which your pharmacist can help you locate.
Some medications may come with an additional patient information leaflet, so it is a good idea to check with your pharmacist for more information. If you have any questions or concerns about your medication, consult with your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. Be prepared to provide information about the medication taken, the amount, and the time it was taken to ensure prompt and effective treatment.