Oyst-Cal 500 W/vitamin D Tablets
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
Calcium Salt; Vitamin D Analog (Cholecalciferol)
Pregnancy Category
Not formally assigned; essential nutrient, generally considered safe at recommended doses. Consult physician for specific supplementation needs.
FDA Approved
Jan 1970
DEA Schedule
Not Controlled
Overview
What is this medicine?
Oyst-Cal 500 W/vitamin D is a supplement that provides calcium and vitamin D. Calcium is important for strong bones and teeth, and vitamin D helps your body absorb and use calcium. It's often used to prevent or treat calcium and vitamin D deficiencies, especially for bone health.
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 to ensure proper absorption.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, avoiding bathrooms and areas where children and pets can access it. Keep all medications in a safe location and out of 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 by your pharmacist. Instead, check with your pharmacist for guidance on the best disposal method or participate in a local drug take-back program if available.
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 dose.
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take this medication with food to ensure proper absorption.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, avoiding bathrooms and areas where children and pets can access it. Keep all medications in a safe location and out of 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 by your pharmacist. Instead, check with your pharmacist for guidance on the best disposal method or participate in a local drug take-back program if available.
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 dose.
Lifestyle & Tips
- Take with food to improve absorption, especially for calcium carbonate.
- If taking more than 500-600 mg of elemental calcium at once, divide the dose throughout the day for better absorption.
- Separate from other medications (especially antibiotics, thyroid hormones, bisphosphonates) by at least 2-4 hours.
- Maintain a balanced diet rich in calcium (dairy, leafy greens) and vitamin D (fatty fish, fortified foods).
- Engage in regular weight-bearing exercise to support bone health.
- Limit excessive alcohol intake and smoking, which can negatively impact bone density.
Available Forms & Alternatives
Available Strengths:
Dosing & Administration
Adult Dosing
Standard Dose:
Typically 1-2 tablets daily, providing 500-1000 mg elemental calcium and 200-800 IU Vitamin D3, depending on product formulation and individual needs.
Dose Range:
500 - 1200 mg
Condition-Specific Dosing:
osteoporosisPrevention:
1000-1200 mg elemental calcium and 600-800 IU Vitamin D3 daily
dietaryDeficiency:
Dose adjusted based on dietary intake and serum levels
Pediatric Dosing
Neonatal:
Not established (specific pediatric formulations/doses required)
Infant:
Not established (specific pediatric formulations/doses required)
Child:
Dosing based on age-specific Recommended Dietary Allowances (RDAs). E.g., 700-1000 mg elemental calcium and 600 IU Vitamin D3 daily for children 4-8 years.
Adolescent:
1300 mg elemental calcium and 600 IU Vitamin D3 daily for ages 9-18 years.
Dose Adjustments
Renal Impairment:
Mild:
Use with caution; monitor serum calcium and phosphate.
Moderate:
Use with caution; monitor serum calcium and phosphate. May require dose adjustment or alternative forms of Vitamin D (e.g., calcitriol).
Severe:
Contraindicated in severe hypercalcemia or hypercalciuria. Use with extreme caution; monitor serum calcium, phosphate, and PTH closely. May require active Vitamin D metabolites.
Dialysis:
Use with extreme caution; monitor serum calcium and phosphate closely. Calcium-based binders may contribute to hypercalcemia. Vitamin D supplementation should be managed by a nephrologist.
Hepatic Impairment:
Mild:
No specific adjustment typically needed.
Moderate:
No specific adjustment typically needed, but severe impairment may affect Vitamin D activation (25-hydroxylation).
Severe:
May impair 25-hydroxylation of Vitamin D. Monitor Vitamin D levels and consider activated forms if deficiency persists.
Pharmacology
Mechanism of Action
Calcium is an essential mineral for bone formation, maintenance, and various physiological processes including nerve transmission, muscle contraction, and blood coagulation. Vitamin D (cholecalciferol) is a fat-soluble vitamin that plays a crucial role in calcium and phosphate homeostasis. It promotes calcium absorption from the gut, facilitates calcium reabsorption in the kidneys, and is essential for proper bone mineralization and remodeling. Vitamin D also has roles in immune function and cell growth.
Pharmacokinetics
Absorption:
Bioavailability:
Calcium: Approximately 20-40% (varies with dose, food, and individual factors). Vitamin D: Readily absorbed from the small intestine (requires bile salts).
Tmax:
Calcium: 1-2 hours (for serum calcium peak after oral dose). Vitamin D: 10-12 hours (for cholecalciferol), 2-3 days (for 25-hydroxyvitamin D).
FoodEffect:
Calcium absorption is enhanced when taken with food. Vitamin D absorption is enhanced by dietary fat.
Distribution:
Vd:
Calcium: Primarily in bone (99%). Vitamin D: Widely distributed, stored in adipose tissue and muscle.
ProteinBinding:
Calcium: Approximately 40-50% bound to plasma proteins (albumin). Vitamin D: Cholecalciferol and its metabolites are highly protein-bound, primarily to vitamin D-binding protein (DBP).
CnssPenetration:
Limited for calcium; Vitamin D metabolites can cross the blood-brain barrier.
Elimination:
HalfLife:
Calcium: Complex, depends on physiological state. Vitamin D (cholecalciferol): Approximately 24 hours. 25-hydroxyvitamin D: 2-3 weeks. 1,25-dihydroxyvitamin D: 4-6 hours.
Clearance:
Not typically quantified for calcium. Vitamin D metabolites are cleared primarily via biliary excretion.
ExcretionRoute:
Calcium: Primarily fecal (unabsorbed), renal (filtered and reabsorbed). Vitamin D: Primarily biliary/fecal excretion of metabolites; minor renal excretion.
Unchanged:
Minimal for Vitamin D; most is metabolized.
Pharmacodynamics
OnsetOfAction:
Calcium: Rapid (within minutes for acute effects on nerve/muscle). Vitamin D: Days to weeks for significant changes in serum calcium/phosphate levels and bone mineralization.
PeakEffect:
Calcium: Hours. Vitamin D: Weeks to months for full therapeutic effect on bone density.
DurationOfAction:
Calcium: Hours. Vitamin D: Weeks to months (due to storage and slow turnover of metabolites).
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
Although rare, some people may experience severe and potentially life-threatening side effects while 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
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor 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 list is not exhaustive, and you may experience other side effects not mentioned here. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while 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
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor 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 list is not exhaustive, and you may experience other side effects not mentioned here. If you have questions or concerns about side effects, consult 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 too much calcium (hypercalcemia): Nausea, vomiting, constipation, loss of appetite, increased thirst, increased urination, muscle weakness, fatigue, confusion.
- Signs of kidney stones: Severe pain in your back or side, blood in your urine, painful urination, fever, chills.
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, any of 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 with all your other medications and health conditions. Never start, stop, or change the dose 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, any of 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 with all your other medications and health conditions. Never start, stop, or change the dose 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 advise you to take other oral medications at a different time than this drug. 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, inform your doctor. You and your doctor will need to discuss the potential benefits and risks of this medication to both you and your baby to make an informed decision about its use.
When taking this medication, be aware that it may interfere with the absorption of other oral medications. To minimize potential interactions, your doctor may advise you to take other oral medications at a different time than this drug. 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, inform your doctor. You and your doctor will need to discuss the potential benefits and risks of this medication to both you and your baby to make an informed decision about its use.
Overdose Information
Overdose Symptoms:
- Severe hypercalcemia symptoms (as listed above)
- Kidney problems (e.g., kidney stones, impaired kidney function)
- Heart rhythm abnormalities (rare, severe cases)
- Soft tissue calcification (with chronic excessive intake)
What to Do:
If you suspect an overdose, seek immediate medical attention or call a poison control center (e.g., 1-800-222-1222 in the US). Treatment may involve stopping the supplement, increasing fluid intake, and in severe cases, medical interventions to lower calcium levels.
Drug Interactions
Major Interactions
- Tetracycline antibiotics (e.g., doxycycline, minocycline): Calcium can chelate these antibiotics, significantly reducing their absorption. Separate administration by at least 2-4 hours.
- Fluoroquinolone antibiotics (e.g., ciprofloxacin, levofloxacin): Similar to tetracyclines, calcium can chelate these, reducing absorption. Separate administration by at least 2-6 hours.
- Bisphosphonates (e.g., alendronate, risedronate): Calcium can interfere with bisphosphonate absorption. Separate administration by at least 30 minutes to 2 hours (check specific bisphosphonate instructions).
- Thyroid hormones (e.g., levothyroxine): Calcium can impair absorption. Separate administration by at least 4 hours.
- Digoxin: Hypercalcemia (from excessive calcium/Vitamin D) can increase the risk of digoxin toxicity.
Moderate Interactions
- Thiazide diuretics (e.g., hydrochlorothiazide): Can decrease urinary calcium excretion, increasing risk of hypercalcemia.
- Corticosteroids (e.g., prednisone): Can decrease calcium absorption and increase calcium excretion, potentially increasing Vitamin D requirements.
- Phenytoin, carbamazepine, barbiturates: Can increase Vitamin D metabolism, potentially leading to Vitamin D deficiency.
- Orlistat, cholestyramine, mineral oil: Can reduce absorption of fat-soluble Vitamin D.
- Iron supplements, Zinc supplements: Calcium can interfere with their absorption. Separate administration by several hours.
- Proton pump inhibitors (e.g., omeprazole): Long-term use may reduce calcium absorption (especially calcium carbonate).
Minor Interactions
- Fiber-rich foods (e.g., bran): May slightly reduce calcium absorption.
- Oxalic acid (spinach, rhubarb) and phytic acid (whole grains, legumes): Can bind calcium and reduce absorption.
Monitoring
Baseline Monitoring
Serum Calcium (total and/or ionized)
Rationale: To establish baseline levels and identify pre-existing hypercalcemia or hypocalcemia.
Timing: Before initiating supplementation, especially with higher doses or in patients with renal impairment.
Serum 25-hydroxyvitamin D (25-OH D)
Rationale: To assess baseline Vitamin D status and guide dosing.
Timing: Before initiating supplementation, especially if deficiency is suspected or being treated.
Renal Function (Serum Creatinine, eGFR)
Rationale: To assess kidney function, as renal impairment affects calcium and Vitamin D metabolism and excretion, increasing hypercalcemia risk.
Timing: Before initiating supplementation, particularly in elderly or those with risk factors for kidney disease.
Routine Monitoring
Serum Calcium (total and/or ionized)
Frequency: Periodically (e.g., every 3-6 months) for patients on higher doses or with risk factors for hypercalcemia; annually for routine supplementation.
Target: 8.5-10.2 mg/dL (2.1-2.55 mmol/L)
Action Threshold: If consistently above upper limit of normal, consider dose reduction or discontinuation.
Serum 25-hydroxyvitamin D (25-OH D)
Frequency: Every 3-6 months until target level achieved, then annually for maintenance, especially if treating deficiency.
Target: >30 ng/mL (75 nmol/L)
Action Threshold: If below target, consider dose increase; if above 100 ng/mL, consider dose reduction to avoid toxicity.
Renal Function (Serum Creatinine, eGFR)
Frequency: Annually, or more frequently in patients with pre-existing renal impairment or those developing hypercalcemia.
Target: Stable eGFR, within normal limits for age.
Action Threshold: Significant decline in eGFR or signs of renal dysfunction warrant investigation and dose review.
Symptom Monitoring
- Symptoms of hypercalcemia: Nausea, vomiting, constipation, abdominal pain, loss of appetite, excessive thirst, frequent urination, muscle weakness, fatigue, confusion, bone pain.
- Symptoms of kidney stones: Severe back or side pain, blood in urine, painful urination, fever, chills.
Special Patient Groups
Pregnancy
Calcium and Vitamin D are essential nutrients during pregnancy for fetal bone development and maternal health. Supplementation is generally safe and often recommended to meet increased needs, but excessive doses should be avoided. Consult with a healthcare provider to determine appropriate dosing.
Trimester-Specific Risks:
First Trimester:
Essential for early fetal development; generally safe at recommended doses.
Second Trimester:
Continued importance for fetal skeletal growth; generally safe at recommended doses.
Third Trimester:
Crucial for rapid fetal bone mineralization; generally safe at recommended doses.
Lactation
Calcium and Vitamin D are excreted into breast milk and are essential for infant growth and maternal bone health. Supplementation at recommended doses is generally safe and beneficial for lactating mothers and their infants. Consult with a healthcare provider.
Infant Risk:
Low risk at recommended maternal doses; beneficial for infant's calcium and Vitamin D intake.
Pediatric Use
Dosing must be carefully adjusted based on age, weight, and specific dietary intake to meet age-specific RDAs. Excessive intake can lead to hypercalcemia and potential adverse effects. Always consult a pediatrician before administering to children.
Geriatric Use
Elderly individuals are at higher risk for calcium and Vitamin D deficiency due to decreased dietary intake, reduced skin synthesis of Vitamin D, and impaired renal activation of Vitamin D. Supplementation is often recommended for bone health. However, they may also be more susceptible to hypercalcemia and constipation, requiring careful monitoring of serum calcium and renal function.
Clinical Information
Clinical Pearls
- Calcium carbonate (like in Oyst-Cal) should be taken with food for optimal absorption, as it requires stomach acid. Calcium citrate can be taken with or without food.
- Divide calcium doses if taking more than 500-600 mg elemental calcium at once, as absorption efficiency decreases with larger single doses.
- Remember to account for calcium obtained from dietary sources when calculating total daily intake to avoid excessive supplementation.
- Vitamin D status (25-OH D levels) should be checked, especially if deficiency is suspected or if treating osteoporosis, to guide appropriate Vitamin D dosing.
- Advise patients to separate calcium/Vitamin D supplements from other medications that can interact (e.g., antibiotics, thyroid hormones, bisphosphonates) by at least 2-4 hours.
- Educate patients on symptoms of hypercalcemia to ensure prompt reporting if they occur.
Alternative Therapies
- Dietary calcium (dairy products, fortified foods, leafy greens)
- Dietary Vitamin D (fatty fish, fortified milk/cereals, sun exposure)
- Other calcium salts (e.g., calcium citrate, calcium gluconate)
- Other Vitamin D forms (e.g., Vitamin D2 - ergocalciferol, calcitriol for renal disease)
- Prescription medications for osteoporosis (e.g., bisphosphonates, denosumab, teriparatide) if indicated.
Cost & Coverage
Average Cost:
$5 - $25 per 60-120 tablets
Generic Available:
Yes
Insurance Coverage:
Often not covered by insurance unless prescribed for a specific medical condition (e.g., osteoporosis) or as part of a specific health plan's formulary. Typically considered an over-the-counter (OTC) supplement.
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 happened.