Paricalcitol 1mcg Capsules
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
Pregnancy Category
Category C
FDA Approved
Dec 2000
DEA Schedule
Not Controlled
Overview
What is this medicine?
Paricalcitol is a type of vitamin D that helps control the levels of parathyroid hormone (PTH) in your body. High PTH levels can be a problem for people with kidney disease. This medicine helps lower PTH without causing too much calcium or phosphorus to build up in your blood, which can be harmful.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. You can take this medication with or without food. It's essential to continue taking this medication as directed by your doctor or healthcare provider, even if you're feeling well.
Storing and Disposing of Your Medication
Store this medication at room temperature in a dry place, avoiding the bathroom. Keep all medications in a safe location, out of the reach of children and pets. When disposing of unused or expired medications, do not flush them down the toilet or pour them down the drain unless instructed to do so. Instead, consult your pharmacist for guidance on the best disposal method. You may also want to explore local drug take-back programs.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Avoid taking two doses at the same time or taking extra doses. If you take this medication three times a week and miss a dose, contact your doctor for guidance on what to do next.
To use this medication correctly, follow your doctor's instructions and read all the information provided. You can take this medication with or without food. It's essential to continue taking this medication as directed by your doctor or healthcare provider, even if you're feeling well.
Storing and Disposing of Your Medication
Store this medication at room temperature in a dry place, avoiding the bathroom. Keep all medications in a safe location, out of the reach of children and pets. When disposing of unused or expired medications, do not flush them down the toilet or pour them down the drain unless instructed to do so. Instead, consult your pharmacist for guidance on the best disposal method. You may also want to explore local drug take-back programs.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Avoid taking two doses at the same time or taking extra doses. If you take this medication three times a week and miss a dose, contact your doctor for guidance on what to do next.
Lifestyle & Tips
- Follow your doctor's recommendations for diet, especially regarding calcium and phosphorus intake.
- Avoid over-the-counter calcium or vitamin D supplements unless directed by your doctor.
- Take the medication exactly as prescribed, do not miss doses.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
Initial dose varies by CKD stage and baseline PTH. Titrate based on PTH, calcium, and phosphorus levels.
Dose Range:
1 - 16 mg
Condition-Specific Dosing:
CKD Stage 3/4 (Pre-dialysis):
Initial: 1 mcg daily or 2 mcg three times a week. Adjust by 1 mcg increments every 2-4 weeks to achieve target PTH reduction (e.g., 30% from baseline).
CKD Stage 5 (Dialysis):
Initial: If baseline iPTH < 500 pg/mL, 1 mcg daily or 2 mcg three times a week. If baseline iPTH >= 500 pg/mL, 2 mcg daily or 4 mcg three times a week. Adjust by 1-2 mcg increments every 2-4 weeks to maintain iPTH in target range (e.g., 150-300 pg/mL).
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established (oral capsules)
Dose Adjustments
Renal Impairment:
Mild:
Dosing is inherently for CKD; no specific adjustment beyond standard titration based on PTH, calcium, and phosphorus.
Moderate:
Dosing is inherently for CKD; no specific adjustment beyond standard titration based on PTH, calcium, and phosphorus.
Severe:
Dosing is inherently for CKD; no specific adjustment beyond standard titration based on PTH, calcium, and phosphorus.
Dialysis:
Used in dialysis patients; dose adjusted based on PTH, calcium, and phosphorus levels.
Hepatic Impairment:
Mild:
No specific dose adjustment recommended.
Moderate:
No specific dose adjustment recommended, but caution advised.
Severe:
No specific dose adjustment recommended, but caution advised.
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 target tissues, including the parathyroid glands. This activation suppresses parathyroid hormone (PTH) synthesis and secretion without significantly increasing intestinal calcium and phosphorus absorption, thereby minimizing the risk of hypercalcemia and hyperphosphatemia compared to non-selective vitamin D analogs.
Pharmacokinetics
Absorption:
Bioavailability:
Approximately 72%
Tmax:
2-4 hours
FoodEffect:
Food does not significantly affect absorption.
Distribution:
Vd:
Approximately 3.1 L/kg
ProteinBinding:
>99%
CnssPenetration:
Limited
Elimination:
HalfLife:
Approximately 15-30 hours (terminal)
Clearance:
Not available (primarily biliary excretion)
ExcretionRoute:
Primarily fecal (70%), renal (16%)
Unchanged:
Minimal
Pharmacodynamics
OnsetOfAction:
Not precisely defined for PTH suppression, effects seen within weeks of titration.
PeakEffect:
Not precisely defined for PTH suppression, effects seen within weeks of titration.
DurationOfAction:
Not precisely defined, but half-life suggests daily or thrice-weekly dosing is appropriate.
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 medical attention immediately:
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
Frequent 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 others that concern you or do not go away, contact your doctor or seek medical attention:
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 medical attention immediately:
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
Frequent 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 others that concern you or do not go away, contact your doctor or seek medical attention:
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:
- Nausea
- Vomiting
- Constipation
- Feeling very tired or weak
- Muscle weakness
- Confusion
- Increased thirst or urination
- Bone pain
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, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain health conditions, including 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, so it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter (OTC) 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, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain health conditions, including 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, so it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter (OTC) 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.
Consuming grapefruit juice or eating grapefruit regularly may also interact with this medication, so it is crucial to discuss this with your doctor. To maximize the effectiveness of your treatment, adhere to the diet plan recommended by your doctor.
If you are pregnant or planning to become pregnant, notify your doctor immediately. You will need to have a discussion about the potential benefits and risks of using this medication during pregnancy.
When taking this medication, be aware of potential interactions with other substances. If you are also taking cholestyramine or mineral oil, take this medication at least 1 hour before or 4 to 6 hours after taking cholestyramine or mineral oil to minimize interactions.
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.
Consuming grapefruit juice or eating grapefruit regularly may also interact with this medication, so it is crucial to discuss this with your doctor. To maximize the effectiveness of your treatment, adhere to the diet plan recommended by your doctor.
If you are pregnant or planning to become pregnant, notify your doctor immediately. You will need to have a discussion about the potential benefits and risks of using this medication during pregnancy.
When taking this medication, be aware of potential interactions with other substances. If you are also taking cholestyramine or mineral oil, take this medication at least 1 hour before or 4 to 6 hours after taking cholestyramine or mineral oil to minimize interactions.
Overdose Information
Overdose Symptoms:
- Hypercalcemia (nausea, vomiting, anorexia, constipation, lethargy, muscle weakness, confusion, polyuria, polydipsia, dehydration, stupor, coma)
- Hyperphosphatemia
What to Do:
Discontinue paricalcitol, monitor serum calcium and phosphorus, hydrate, consider loop diuretics, corticosteroids, or calcitonin. Dialysis may be needed in severe cases. Call 1-800-222-1222 (Poison Control).
Drug Interactions
Major Interactions
- CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin, ritonavir)
- Calcium-containing phosphate binders
- Magnesium-containing products (e.g., antacids, laxatives)
Moderate Interactions
- Thiazide diuretics
- Digitalis glycosides
Monitoring
Baseline Monitoring
Serum Calcium
Rationale: To establish baseline and monitor for hypercalcemia.
Timing: Prior to initiation
Serum Phosphorus
Rationale: To establish baseline and monitor for hyperphosphatemia.
Timing: Prior to initiation
Intact Parathyroid Hormone (iPTH)
Rationale: To establish baseline and guide initial dosing and titration.
Timing: Prior to initiation
25-hydroxyvitamin D
Rationale: To assess vitamin D status and guide supplementation if needed.
Timing: Prior to initiation
Alkaline Phosphatase
Rationale: To assess bone turnover.
Timing: Prior to initiation
Routine Monitoring
Serum Calcium
Frequency: At least twice weekly initially, then monthly
Target: 8.4-10.2 mg/dL
Action Threshold: Hold or reduce dose if hypercalcemia occurs (e.g., >10.2 mg/dL or clinically significant increase).
Serum Phosphorus
Frequency: At least twice weekly initially, then monthly
Target: 2.5-4.5 mg/dL
Action Threshold: Hold or reduce dose if hyperphosphatemia occurs (e.g., >4.5 mg/dL or clinically significant increase).
Intact Parathyroid Hormone (iPTH)
Frequency: Every 2-4 weeks initially, then every 1-3 months
Target: CKD Stage 5: 150-300 pg/mL; CKD Stage 3/4: 30-60% reduction from baseline
Action Threshold: Adjust dose to achieve and maintain target range.
Symptom Monitoring
- Nausea
- Vomiting
- Constipation
- Lethargy
- Muscle weakness
- Confusion
- Increased thirst
- Increased urination
- Bone pain
Special Patient Groups
Pregnancy
Category C. Use only if the potential benefit justifies the potential risk to the fetus. Animal studies have shown adverse effects at high doses.
Trimester-Specific Risks:
First Trimester:
Risk not specifically differentiated, general caution.
Second Trimester:
Risk not specifically differentiated, general caution.
Third Trimester:
Risk not specifically differentiated, general caution.
Lactation
It is unknown if paricalcitol is excreted in human milk. Caution should be exercised when paricalcitol is administered to a nursing woman. Consider the benefits of breastfeeding versus the potential risks to the infant.
Infant Risk:
Low to moderate risk; monitor infant for signs of hypercalcemia.
Pediatric Use
Safety and efficacy of oral paricalcitol capsules have not been established in pediatric patients. The intravenous formulation has been studied in adolescents.
Geriatric Use
No overall differences in safety or effectiveness were observed between elderly and younger patients. However, greater sensitivity of some older individuals cannot be ruled out. Dose selection should be cautious, generally starting at the low end of the dosing range.
Clinical Information
Clinical Pearls
- Paricalcitol is a selective vitamin D receptor activator, designed to suppress PTH with less impact on serum calcium and phosphorus levels compared to non-selective vitamin D analogs.
- Close and frequent monitoring of serum calcium, phosphorus, and iPTH is crucial for safe and effective use, especially during dose titration.
- Hypercalcemia and hyperphosphatemia are the primary adverse effects and require prompt dose adjustment or temporary discontinuation.
- Patients should be advised to avoid calcium-containing antacids, other calcium supplements, or vitamin D supplements without consulting their healthcare provider.
Alternative Therapies
- Other vitamin D receptor activators (e.g., calcitriol, doxercalciferol)
- Calcimimetics (e.g., cinacalcet, etelcalcetide) for severe secondary hyperparathyroidism
- Phosphate binders (often used concurrently to manage hyperphosphatemia)
Cost & Coverage
Average Cost:
Varies, typically several hundred dollars per 30 capsules
Generic Available:
Yes
Insurance Coverage:
Tier 3 or 4 (may require prior authorization)
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it's a good idea to check with your pharmacist for more information. If you have any questions or concerns about this medication, don't hesitate to discuss them 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. When seeking help, be prepared to provide details about the overdose, including the medication taken, the amount, and the time it occurred.