Oyster Shell Calcium 250mg W/d Tabs
It is used to help growth and good health.It is used to prevent or treat soft, brittle bones (osteoporosis).It is used to treat or prevent low calcium levels.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Mineral/Vitamin Supplement, Bone Health Agent
Pharmacologic Class
Mineral Supplement, Vitamin D Analog
Pregnancy Category
Category A (at recommended doses); C (at higher doses)
FDA Approved
Jan 1970
DEA Schedule
Not Controlled
Overview
What is this medicine?
This supplement provides calcium, an essential mineral for building and maintaining strong bones and teeth, and Vitamin D, which is crucial for your body to absorb and use calcium effectively. It's commonly used to prevent or treat calcium and Vitamin D deficiencies, especially to support overall bone health and reduce the risk of osteoporosis.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take this medication with food as directed.
Storing and Disposing of Your Medication
Store this medication at room temperature in a dry location, avoiding the bathroom. Keep all medications in a safe place, out of the reach of children and pets. When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so. Instead, consult your pharmacist for guidance on proper disposal. You may also want to check if there are drug take-back programs available in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it is close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for a missed one.
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take this medication with food as directed.
Storing and Disposing of Your Medication
Store this medication at room temperature in a dry location, avoiding the bathroom. Keep all medications in a safe place, out of the reach of children and pets. When disposing of unused or expired medication, do not flush it down the toilet or pour it down the drain unless instructed to do so. Instead, consult your pharmacist for guidance on proper disposal. You may also want to check if there are drug take-back programs available in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it is close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for a missed one.
Lifestyle & Tips
- Take calcium carbonate (like oyster shell calcium) with food to enhance absorption.
- Maintain adequate fluid intake to help prevent kidney stones.
- Engage in regular weight-bearing exercise to support bone health.
- Ensure a balanced diet rich in calcium and Vitamin D from food sources.
- Separate dosing from other medications (e.g., iron, thyroid hormones, certain antibiotics) by at least 2-4 hours to avoid absorption issues.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
Dosage varies based on individual needs and dietary intake. For Oyster Shell Calcium 250mg W/D Tabs, typically 1-4 tablets daily (providing 250-1000 mg elemental calcium and associated Vitamin D), often divided, with food.
Dose Range:
250 - 1000 mg
Condition-Specific Dosing:
osteoporosis_prevention:
500-1000 mg elemental calcium and 600-800 IU Vitamin D daily
calcium_deficiency:
Individualized based on severity
Pediatric Dosing
Neonatal:
Not established (requires specific medical guidance)
Infant:
Dosage based on age-specific Recommended Dietary Allowances (RDAs) and clinical need, typically under medical supervision.
Child:
Dosage based on age-specific Recommended Dietary Allowances (RDAs) and clinical need, typically under medical supervision.
Adolescent:
Dosage based on age-specific Recommended Dietary Allowances (RDAs) and clinical need, typically under medical supervision.
Dose Adjustments
Renal Impairment:
Mild:
Use with caution; monitor serum calcium and phosphate. Dose adjustment may be necessary.
Moderate:
Use with caution; monitor serum calcium and phosphate. Dose adjustment may be necessary, especially for Vitamin D, to avoid hypercalcemia.
Severe:
Contraindicated or requires careful monitoring and individualized dosing, often with active Vitamin D forms, due to high risk of hypercalcemia and hyperphosphatemia.
Dialysis:
Requires careful monitoring and individualized dosing, often with active Vitamin D forms (e.g., calcitriol), and phosphate binders.
Hepatic Impairment:
Mild:
Generally no specific dose adjustment for calcium.
Moderate:
Generally no specific dose adjustment for calcium. Vitamin D metabolism may be altered in severe hepatic disease; monitor levels.
Severe:
Generally no specific dose adjustment for calcium. Vitamin D metabolism may be significantly altered; monitor Vitamin D levels and calcium closely.
Pharmacology
Mechanism of Action
Calcium is an essential mineral for bone formation, nerve impulse transmission, muscle contraction, and blood coagulation. Vitamin D (cholecalciferol) is a fat-soluble vitamin that promotes intestinal absorption of calcium and phosphate, regulates bone mineralization, and helps maintain serum calcium and phosphate homeostasis.
Pharmacokinetics
Absorption:
Bioavailability:
Calcium (as carbonate): Approximately 20-40% (enhanced by food). Vitamin D: High (fat-soluble).
Tmax:
Calcium: 1-2 hours. Vitamin D: 4-5 hours (cholecalciferol).
FoodEffect:
Calcium carbonate absorption is enhanced by stomach acid produced with food. Vitamin D absorption is enhanced by dietary fat.
Distribution:
Vd:
Calcium: Not typically reported as Vd (primarily in bone). Vitamin D: Large (stored in adipose tissue and muscle).
ProteinBinding:
Calcium: Approximately 40% bound to albumin. Vitamin D: Primarily bound to vitamin D-binding protein (DBP).
CnssPenetration:
Limited for calcium. Vitamin D metabolites can cross the blood-brain barrier.
Elimination:
HalfLife:
Calcium: Not applicable (homeostatically regulated). Vitamin D (cholecalciferol): ~24 hours; 25(OH)D: ~15-30 days; 1,25(OH)2D: ~4-6 hours.
Clearance:
Not typically reported for calcium. Vitamin D: Hepatic and renal.
ExcretionRoute:
Calcium: Primarily fecal, some renal. Vitamin D: Primarily biliary/fecal, some renal.
Unchanged:
Calcium: N/A. Vitamin D: Minimal unchanged excretion.
Pharmacodynamics
OnsetOfAction:
Calcium: Rapid (minutes for acute effects on nerve/muscle), weeks-months for bone density changes. Vitamin D: Days to weeks for full effect on calcium absorption.
PeakEffect:
Calcium: Hours. Vitamin D: Weeks.
DurationOfAction:
Calcium: Hours. Vitamin D: Weeks to months (due to storage and metabolite half-lives).
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
Although rare, this medication can cause severe and potentially life-threatening side effects. If you experience 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
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only have mild ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or do not go away, contact your doctor:
Upset stomach or vomiting
Constipation
Note: This is not an exhaustive list of all possible side effects. If you have questions or concerns about side effects, consult your doctor. For medical advice about side effects, you can also contact your doctor. Additionally, you can report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, this medication can cause severe and potentially life-threatening side effects. If you experience 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
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only have mild ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or do not go away, contact your doctor:
Upset stomach or vomiting
Constipation
Note: This is not an exhaustive list of all possible side effects. If you have questions or concerns about side effects, consult your doctor. For medical advice about side effects, you can also contact your doctor. Additionally, you can 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:
- Severe constipation
- Persistent nausea or vomiting
- Unusual fatigue or muscle weakness
- Excessive thirst or urination
- Confusion or changes in mental status
- Abdominal 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
+ High vitamin D levels
+ Kidney stones
+ Low phosphate levels
This list is not exhaustive, and it is crucial to discuss all your health problems with your doctor.
Additionally, provide your doctor and pharmacist with a comprehensive list of all the medications you are taking, including:
Prescription medications
Over-the-counter (OTC) medications
Natural products
Vitamins
It is vital to verify that it is safe to take this medication in conjunction with all your other medications and health conditions. Never start, stop, or adjust the dosage of any medication without first consulting 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
+ High vitamin D levels
+ Kidney stones
+ Low phosphate levels
This list is not exhaustive, and it is crucial to discuss all your health problems with your doctor.
Additionally, provide your doctor and pharmacist with a comprehensive list of all the medications you are taking, including:
Prescription medications
Over-the-counter (OTC) medications
Natural products
Vitamins
It is vital to verify that it is safe to take this medication in conjunction with all your other medications and health conditions. Never start, stop, or adjust the dosage of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. If you have a known allergy to tartrazine (also referred to as FD&C Yellow No. 5), consult with your doctor, as some formulations of this drug may contain this ingredient.
When taking this medication, be aware that it may interfere with the absorption of other oral medications. To minimize potential interactions, your doctor may recommend taking other oral drugs at a different time than this medication. Discuss your medication schedule with your doctor to ensure safe and effective use.
Adhere to the dietary plan recommended by your doctor to optimize the benefits of this medication. Additionally, if you are pregnant, planning to become pregnant, or are breast-feeding, notify your doctor. A discussion about the potential benefits and risks of this medication to both you and your baby is necessary to make an informed decision.
When taking this medication, be aware that it may interfere with the absorption of other oral medications. To minimize potential interactions, your doctor may recommend taking other oral drugs at a different time than this medication. Discuss your medication schedule with your doctor to ensure safe and effective use.
Adhere to the dietary plan recommended by your doctor to optimize the benefits of this medication. Additionally, if you are pregnant, planning to become pregnant, or are breast-feeding, notify your doctor. A discussion about the potential benefits and risks of this medication to both you and your baby is necessary to make an informed decision.
Overdose Information
Overdose Symptoms:
- Anorexia
- Nausea
- Vomiting
- Constipation
- Abdominal pain
- Muscle weakness
- Fatigue
- Polyuria
- Polydipsia
- Mental status changes (confusion, lethargy)
- Kidney stones
- Cardiac arrhythmias (in severe cases)
What to Do:
Discontinue the supplement immediately. Seek urgent medical attention. Treatment involves hydration, diuresis, and potentially other medications to lower calcium levels. Call 1-800-222-1222 (Poison Control Center) for advice.
Drug Interactions
Contraindicated Interactions
- Hypercalcemia
- Hypervitaminosis D
- Severe renal impairment (without close monitoring)
Major Interactions
- Thiazide diuretics (increased risk of hypercalcemia)
- Digoxin (increased risk of cardiac arrhythmias with hypercalcemia)
- Calcipotriene (increased risk of hypercalcemia)
Moderate Interactions
- Tetracyclines (reduced antibiotic absorption; separate dosing by 2-4 hours)
- Fluoroquinolones (reduced antibiotic absorption; separate dosing by 2-4 hours)
- Levothyroxine (reduced thyroid hormone absorption; separate dosing by 4 hours)
- Bisphosphonates (reduced bisphosphonate absorption; separate dosing by 30-60 minutes)
- Iron supplements (reduced iron absorption; separate dosing by 2-4 hours)
- Phenytoin, Barbiturates (increased Vitamin D metabolism, potentially reducing efficacy)
- Orlistat, Cholestyramine (reduced Vitamin D absorption)
- Corticosteroids (reduced calcium absorption)
- Mineral oil (reduced Vitamin D absorption)
Minor Interactions
- Antacids containing aluminum (may increase calcium absorption, but also risk of hypercalcemia with prolonged use)
Monitoring
Baseline Monitoring
Serum Calcium (total and ionized)
Rationale: To establish baseline and identify pre-existing hypercalcemia.
Timing: Prior to initiation
Serum Phosphate
Rationale: To establish baseline and assess mineral balance.
Timing: Prior to initiation
Serum 25-hydroxyvitamin D
Rationale: To assess baseline Vitamin D status and guide dosing.
Timing: Prior to initiation
Renal function (Serum Creatinine, BUN)
Rationale: To assess kidney function, as renal impairment affects calcium and Vitamin D metabolism and excretion.
Timing: Prior to initiation
Routine Monitoring
Serum Calcium (total)
Frequency: Every 3-6 months initially, then annually, or as clinically indicated.
Target: 8.5-10.2 mg/dL (or laboratory specific range)
Action Threshold: >10.5 mg/dL (consider dose reduction or discontinuation, investigate cause)
Serum 25-hydroxyvitamin D
Frequency: Every 6-12 months, or as clinically indicated, until target levels are achieved and maintained.
Target: 30-100 ng/mL (or 75-250 nmol/L)
Action Threshold: >100 ng/mL (consider dose reduction or discontinuation to avoid toxicity)
Renal function (Serum Creatinine)
Frequency: Annually, or more frequently in patients with pre-existing renal impairment or risk factors.
Target: Stable within normal limits
Action Threshold: Significant increase in creatinine (re-evaluate dosing, especially in severe impairment)
Symptom Monitoring
- Nausea
- Vomiting
- Constipation
- Polyuria (frequent urination)
- Polydipsia (excessive thirst)
- Muscle weakness
- Fatigue
- Confusion
- Loss of appetite
- Abdominal pain
Special Patient Groups
Pregnancy
Calcium and Vitamin D are essential nutrients during pregnancy for both maternal and fetal health. Recommended daily allowances should be met through diet and supplementation if necessary. Excessive doses should be avoided due to potential risks of hypercalcemia in the mother and fetus.
Trimester-Specific Risks:
First Trimester:
Essential for early fetal development and skeletal formation.
Second Trimester:
Continued importance for rapid fetal bone growth and mineralization.
Third Trimester:
Increased maternal calcium needs due to significant fetal calcium accretion. Risks primarily associated with excessive intake leading to maternal and fetal hypercalcemia.
Lactation
Calcium and Vitamin D are essential nutrients for lactating mothers and are excreted in breast milk. Supplementation at recommended doses is generally considered safe and beneficial for both mother and infant.
Infant Risk:
Low risk to the infant at recommended maternal doses. High maternal doses could theoretically lead to hypercalcemia in the infant, but this is rare.
Pediatric Use
Essential for growth, bone development, and prevention of rickets. Dosing must be age-appropriate based on Recommended Dietary Allowances (RDAs). Close monitoring is required to avoid excessive intake and hypercalcemia.
Geriatric Use
Increased risk of osteoporosis and Vitamin D deficiency. May require higher doses of Vitamin D to achieve adequate levels. Monitor closely for hypercalcemia, especially in those with impaired renal function or on concomitant medications (e.g., thiazide diuretics).
Clinical Information
Clinical Pearls
- Oyster shell calcium is primarily calcium carbonate, which is best absorbed when taken with food due to its requirement for stomach acid.
- Separate calcium supplements from iron, thyroid hormones, and certain antibiotics (e.g., tetracyclines, fluoroquinolones) by at least 2-4 hours to prevent absorption interference.
- Regular monitoring of serum calcium and Vitamin D (25-hydroxyvitamin D) levels is crucial, especially in patients with renal impairment, those taking high doses, or those on interacting medications.
- Adequate Vitamin D status is essential for optimal calcium absorption and utilization; ensure both nutrients are sufficient.
- Encourage dietary sources of calcium (e.g., dairy products, fortified foods, leafy greens) and Vitamin D (e.g., fatty fish, fortified milk, sun exposure) before relying solely on supplements.
Alternative Therapies
- Dietary calcium (e.g., dairy, fortified plant-based milks, leafy greens)
- Dietary Vitamin D (e.g., fatty fish, fortified cereals, sun exposure)
- Bisphosphonates (for osteoporosis treatment)
- Calcitonin (for osteoporosis treatment)
- Parathyroid hormone (PTH) analogs (for severe osteoporosis)
Cost & Coverage
Average Cost:
Varies widely by brand, retailer, and quantity, typically $5-$20 per 60-120 tablets
Generic Available:
Yes
Insurance Coverage:
Generally not covered by prescription drug insurance plans; may be eligible for reimbursement through Flexible Spending Accounts (FSA) or Health Savings Accounts (HSA). Some medical plans might cover for specific medical conditions (e.g., severe deficiency) with a prescription.
General Drug Facts
If your symptoms or health issues persist or worsen, it's 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 be sure to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it occurred.