Usage
Alendronic acid + calcium + vitamin D3 is prescribed for the treatment and prevention of osteoporosis, particularly in postmenopausal women and in men. It also helps increase bone mass and reduce the risk of fractures, including hip and spine fractures, in individuals at risk. It is also utilized for glucocorticoid-induced osteoporosis. This combination specifically targets postmenopausal women at risk of vitamin D insufficiency. This medication belongs to the bisphosphonate class of drugs, combined with essential minerals.
Alendronic acid inhibits osteoclast-mediated bone resorption, while vitamin D3 enhances calcium absorption. Calcium is vital for bone health. This combined action leads to increased bone mineral density and reduced fracture risk.
Alternate Names
While “Alendronic acid + calcium + vitamin D3” accurately describes the drug’s composition, alendronate sodium trihydrate + colecalciferol is a more chemically precise term. Brand names include Fosavance, Ostomax D, and Alen D, among others. A combination pack containing separate tablets for alendronate and calcium/vitamin D3 may be marketed under various brand names.
How It Works
Pharmacodynamics: Alendronic acid, a bisphosphonate, binds to hydroxyapatite on bone surfaces, preferentially at sites of active resorption. It inhibits osteoclast activity, reducing bone turnover and thereby increasing bone mass. Cholecalciferol (vitamin D3) gets converted to calcitriol, the active form of vitamin D. Calcitriol enhances intestinal calcium absorption and plays a vital role in bone mineralization. Calcium is a fundamental component of the bone matrix.
Pharmacokinetics: Alendronate has low bioavailability and its absorption is reduced by food and other medications. It gets rapidly distributed to bone or excreted in the urine. Vitamin D3 is absorbed from the gut and undergoes hepatic and renal metabolism. Alendronate is not metabolized and is primarily excreted unchanged in urine. Both vitamin D and calcium are important for maintaining serum calcium homeostasis.
Mode of action: Alendronate directly inhibits osteoclast activity. Vitamin D indirectly influences bone metabolism by promoting calcium absorption and modulating bone remodeling. Calcium provides the structural building blocks for bone. No direct receptor binding or enzyme inhibition is associated with calcium.
Elimination: Alendronate is primarily excreted unchanged in the urine. Vitamin D metabolites are eliminated through biliary and renal routes.
Dosage
Standard Dosage
Adults:
The standard dosage for osteoporosis treatment and prevention is one 70 mg alendronate + 2800 IU (or 5600 IU) vitamin D3 tablet once weekly. The higher vitamin D dose (5600 IU) is generally preferred for patients not taking supplemental vitamin D. The tablet should be taken on an empty stomach, at least 30 minutes before the first food, drink, or other medication of the day. It must be swallowed whole with plain water, remaining upright for at least 30 minutes after ingestion.
Children:
Alendronic acid + calcium + vitamin D3 is not recommended for use in children under 18. Safety and efficacy have not been established in this population.
Special Cases:
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Elderly Patients: No dosage adjustment is necessary for the elderly.
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Patients with Renal Impairment: Dose adjustment may be necessary for patients with creatinine clearance less than 35 ml/min. Not recommended for patients with severe renal impairment.
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Patients with Hepatic Dysfunction: No dosage adjustment is generally required.
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Patients with Comorbid Conditions: Patients with esophageal disorders, hypocalcemia, or inability to remain upright should not take this medication. Caution is advised in patients with gastrointestinal issues. Correct existing vitamin D deficiency before starting the medication. Monitor calcium and vitamin D levels in patients taking glucocorticoids. Patients with certain conditions, such as sarcoidosis, leukemia, and lymphoma should be monitored for hypercalcemia or hypercalciuria.
Clinical Use Cases
Alendronic acid + calcium + vitamin D3 is specifically indicated for long-term treatment and prevention of osteoporosis and is not intended for acute medical settings like intubation, surgical procedures, mechanical ventilation, ICU use, or emergency situations.
Dosage Adjustments
Dosage adjustments may be needed based on renal function, vitamin D levels, and other patient-specific factors.
Side Effects
Common Side Effects
Gastrointestinal disturbances (abdominal pain, heartburn, nausea, constipation, diarrhea), musculoskeletal pain, headache.
Rare but Serious Side Effects
Esophageal irritation (esophagitis, ulcers, strictures), atypical femoral fractures, osteonecrosis of the jaw, severe hypocalcemia, allergic reactions.
Long-Term Effects
Potential for osteonecrosis of the jaw with long-term use.
Adverse Drug Reactions (ADR)
Esophageal perforation, severe allergic reactions.
Contraindications
Esophageal abnormalities, hypocalcemia, inability to stand or sit upright for at least 30 minutes, hypersensitivity to any components. Pregnancy and breastfeeding.
Drug Interactions
Calcium supplements, antacids, certain oral medications, food, and beverages can interfere with alendronate absorption. Certain medications can also impair vitamin D absorption or metabolism. Consult resources for a detailed list of interactions. Aspirin and NSAIDs may increase the risk of gastrointestinal side effects.
Pregnancy and Breastfeeding
Contraindicated during pregnancy and breastfeeding.
Drug Profile Summary
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Mechanism of Action: Alendronate inhibits bone resorption; vitamin D3 enhances calcium absorption; calcium strengthens bones.
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Side Effects: Gastrointestinal disturbances, musculoskeletal pain, rarely esophageal issues and osteonecrosis of the jaw.
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Contraindications: Esophageal abnormalities, hypocalcemia, inability to stay upright, hypersensitivity.
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Drug Interactions: Calcium/mineral supplements, antacids, some medications can interfere with absorption.
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Pregnancy & Breastfeeding: Contraindicated.
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Dosage: One 70 mg/2800 IU or 70 mg/5600 IU tablet once weekly.
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Monitoring Parameters: Bone mineral density, serum calcium, phosphate, vitamin D, renal function.
Popular Combinations
Often used in conjunction with calcium and vitamin D supplementation when dietary intake is inadequate.
Precautions
Careful attention should be paid to proper administration to avoid esophageal irritation. Correct pre-existing hypocalcemia and other mineral metabolism disorders before starting therapy. Monitor for signs of esophageal issues and osteonecrosis of the jaw. Ensure adequate calcium and vitamin D intake.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Alendronic Acid + Calcium + Vitamin D3?
A: One 70 mg alendronate with either 2800 or 5600 IU Vitamin D3 tablet once weekly, taken on an empty stomach 30 minutes before other intake, with plain water and remaining upright for 30 minutes.
Q2: How does Alendronic Acid + Calcium + Vitamin D3 work?
A: Alendronate inhibits osteoclast activity, reducing bone resorption. Vitamin D promotes calcium absorption. Calcium is a key component of bone.
Q3: What are the common side effects?
A: Abdominal discomfort, heartburn, nausea, constipation, diarrhea, musculoskeletal pain, and headache.
Q4: Who should not take this medication?
A: Patients with esophageal abnormalities, hypocalcemia, inability to sit upright for 30 minutes, or hypersensitivity. Also contraindicated in pregnancy and breastfeeding.
Q5: Are there any drug interactions I should be aware of?
A: Yes, several medications can interact with this combination. Calcium supplements, antacids, and some oral medications can reduce the absorption of alendronate. Refer to drug interaction resources for a comprehensive list.
Q6: What precautions should I advise my patients?
A: Advise patients to take the medication with plain water on an empty stomach, remain upright for at least 30 minutes after ingestion, and ensure adequate calcium and vitamin D intake.
Q7: Can this medication be used in children?
A: No, it’s not recommended for children under 18 due to insufficient data on safety and efficacy.
Q8: How long should treatment with Alendronic Acid + Calcium + Vitamin D3 continue?
A: This medication is intended for long-term use. The duration of therapy should be reassessed periodically, especially after 5 years, weighing benefits against potential risks.
Q9: What should a patient do if they miss a dose?
A: They should take the missed dose the next morning. Do not double up on doses. Return to the regular once-weekly schedule on the chosen day.
Q10: What if my patient has renal impairment?
A: Dosage adjustment might be necessary depending on the degree of impairment. It’s not recommended for patients with severe renal impairment (creatinine clearance < 35 ml/min).
