Usage
- Medical Conditions: This combination is prescribed for the prevention and treatment of hypocalcemia (low blood calcium levels) in patients with insufficient dietary calcium intake. Specific conditions include:
- Osteoporosis (bone loss)
- Osteomalacia/rickets (weak bones)
- Hypoparathyroidism (decreased parathyroid gland activity)
- Latent tetany (a muscle disease)
- Renal osteodystrophy (bone disease in chronic kidney failure)
- Postmenopausal osteoporosis
- Pharmacological Classification: Vitamin and mineral supplement, calcium regulator, vitamin D analog.
- Mechanism of Action: Calcitriol (active form of vitamin D3) increases calcium absorption from the gut and kidneys, regulates calcium and phosphate homeostasis, and stimulates bone mineralization. Calcium citrate malate provides a readily absorbable source of calcium to support these processes.
Alternate Names
- No widely recognized alternate names for the combination product itself, although individual components have various synonyms (e.g., vitamin D3 for cholecalciferol).
- Brand names vary depending on the manufacturer (e.g., Caltrate + D, Os-Cal + D, Citracal + D). Some popular combinations marketed in India are:
- CCM tablets.
- Calcirol sachet.
How It Works
- Pharmacodynamics: Calcitriol binds to vitamin D receptors, modulating gene expression and influencing calcium and phosphate transport in the intestines, kidneys, and bones. Calcium citrate malate provides the necessary calcium for bone mineralization and other physiological processes.
- Pharmacokinetics:
- Absorption: Calcitriol is absorbed orally. Calcium citrate malate absorption is enhanced by vitamin D3. Food can also enhance absorption of both components.
- Metabolism: Calcitriol undergoes hepatic and renal metabolism. Calcium is not metabolized in the traditional sense but is regulated by homeostatic mechanisms.
- Elimination: Calcitriol metabolites are excreted primarily in bile. Calcium is excreted through urine and feces.
- Mode of Action: Calcitriol’s effects are mediated through vitamin D receptor binding, which regulates gene transcription related to calcium and phosphate transport. Calcium citrate malate doesn’t have a specific receptor but acts as a substrate for bone mineralization and other calcium-dependent processes.
- Receptor Binding/Enzyme Inhibition: Calcitriol binds to vitamin D receptors (VDR). No significant enzyme inhibition is associated with this combination.
- Elimination Pathways: Calcitriol is excreted in bile. Calcium is eliminated in urine and feces.
Dosage
Standard Dosage
Adults:
- Varies depending on indication and individual patient needs.
- Typical starting dose: Calcitriol 0.25 mcg daily, with appropriate calcium supplementation.
- Maintenance dose: adjusted based on serum calcium levels and therapeutic response.
- Maximum dose: varies depending on the condition being treated.
Children:
- Dosing based on age and weight. Pediatric use should be supervised by a physician.
- Safety considerations: careful monitoring of serum calcium levels is essential.
Special Cases:
- Elderly Patients: Monitor renal function. Adjust dosage as needed.
- Patients with Renal Impairment: Dose reduction may be needed. Closely monitor calcium and phosphorus levels.
- Patients with Hepatic Dysfunction: Close monitoring is advised, but significant dose adjustments are usually not necessary.
- Patients with Comorbid Conditions: Diabetes, cardiovascular diseases, and other conditions may require individual dose adjustments. Consult with a physician to determine the appropriate dosage.
Clinical Use Cases
Dosing in these settings requires careful evaluation and individualized therapy based on the patient’s condition and response. Consult with a physician regarding the appropriate usage and dosage of this medication in intensive care unit settings.
Dosage Adjustments
Renal or hepatic impairment, hypercalcemia, and concomitant medications require careful monitoring and dose modifications.
Side Effects
Common Side Effects:
- Constipation
- Nausea
- Vomiting
- Headache
- Dry mouth
- Stomach upset
Rare but Serious Side Effects:
- Hypercalcemia (high blood calcium): symptoms include excessive thirst, frequent urination, confusion, fatigue, bone pain.
- Cardiac arrhythmias (irregular heartbeat)
- Allergic reactions (skin rash, itching, hives, swelling).
Long-Term Effects:
- Kidney stones (with prolonged hypercalcemia).
Adverse Drug Reactions (ADR):
Hypercalcemia, cardiac arrhythmias, and allergic reactions are clinically significant ADRs requiring immediate medical attention.
Contraindications
- Hypercalcemia
- Hypervitaminosis D
- Hypersensitivity to calcitriol, calcium citrate malate, or any component of the formulation
- Severe renal impairment
- Metastatic calcification
- Malabsorption syndrome.
Drug Interactions
- Thiazide diuretics (increased risk of hypercalcemia).
- Digoxin (calcium can alter its effects).
- Corticosteroids (may reduce calcium absorption).
- Antacids containing magnesium or aluminum (reduced calcium absorption).
- Tetracycline antibiotics, bisphosphonates, estramustine, levothyroxine, and quinolone antibiotics (calcium can reduce their absorption)
- Bile acid sequestrants, mineral oil, orlistat (reduce vitamin D absorption).
Pregnancy and Breastfeeding
- Pregnancy: Use only if clearly needed, as high doses of vitamin D can have adverse effects on the fetus.
- Breastfeeding: Use with caution. Monitor serum calcium in both mother and infant. The decision to use while breastfeeding requires careful consideration of risks and benefits.
Drug Profile Summary
- Mechanism of Action: Calcitriol enhances calcium and phosphate absorption; calcium citrate malate provides calcium.
- Side Effects: Constipation, nausea, hypercalcemia (serious).
- Contraindications: Hypercalcemia, vitamin D toxicity, severe renal impairment.
- Drug Interactions: Thiazide diuretics, digoxin, corticosteroids, antacids.
- Pregnancy & Breastfeeding: Use with caution; monitor calcium levels.
- Dosage: Varies by indication; requires monitoring and adjustments.
- Monitoring Parameters: Serum calcium, phosphorus, creatinine, PTH.
Popular Combinations
- Vitamin K2 is sometimes added to enhance calcium utilization in bone tissue.
- Other vitamins and minerals are often combined in commercial products.
Precautions
- Renal impairment.
- Hypercalcemia.
- Concomitant medications.
- Pregnancy/breastfeeding.
- Monitor calcium and phosphorus levels.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Calcitriol + Calcium Citrate Malate?
A: Dosage depends on the specific indication and patient factors. A physician should determine the individual dosage. Starting dose for calcitriol is typically 0.25 mcg daily, along with calcium supplementation as needed.
Q2: What are the most common side effects?
A: Constipation, nausea, vomiting, headache, dry mouth and stomach upset are common side effects.
Q3: What are the serious side effects to watch for?
A: Hypercalcemia, characterized by excessive thirst, frequent urination, confusion, fatigue, and bone pain, is a serious side effect requiring immediate medical attention.
Q4: Can this combination be used during pregnancy and breastfeeding?
A: Use with caution. If used during pregnancy, the potential benefit should clearly outweigh the risk to the fetus. If used during breastfeeding, monitor the infant’s calcium levels.
Q5: What are the main drug interactions?
A: Thiazide diuretics, digoxin, corticosteroids, and antacids can interact with this medication.
Q6: What is the role of Calcium Citrate Malate in this combination?
A: Calcium citrate malate provides a readily absorbable source of calcium, essential for bone health and other functions. Calcitriol increases the body’s ability to utilize and retain this calcium.
Q7: How should I monitor patients on this medication?
A: Monitor serum calcium, phosphorus, creatinine, and PTH levels regularly, especially during dose titration.
Q8: Are there any dietary restrictions when taking this medication?
A: Avoid excessive intake of calcium-rich foods, and discuss dietary recommendations with a physician or dietician.
Q9: Can this combination cure fractures?
A: This medication helps to maintain bone health and prevent further bone loss but does not directly heal existing fractures. Fractures are managed through surgical and orthopedic interventions.
Q10: How should the medication be stored?
A: Store the medication in a cool, dry place away from direct sunlight and moisture. Keep out of reach of children.
