OYSTERCAL 500/MG TAB 60/TAB

Benefits & Uses

Primary Benefit

Supports bone strength, dental health, and prevention of calcium deficiency by providing elemental calcium derived from oyster shell.

Health Claims

Contributes to normal bone and teeth maintenance; supports muscle function; essential for normal blood clotting; helps reduce the risk of osteoporosis when combined with adequate Vitamin D

Common Deficiency Symptoms

Muscle cramps and spasms, numbness or tingling in extremities, brittle nails, dental problems, osteopenia, osteoporosis, increased fracture risk, rickets in children

Target Population

Postmenopausal women, elderly adults over 50, individuals with low dietary calcium intake, adolescents during peak bone mass development, pregnant and breastfeeding women, individuals with lactose intolerance avoiding dairy

Scientific Evidence Level

Strong

Onset Timeline

Serum calcium levels normalize within days of supplementation; measurable improvements in bone mineral density require 6-12 months of consistent use

Usage & Dosage

Suggested Use

Take 1 tablet daily with a meal, or as directed by a healthcare professional

Serving Size

1 Film-Coated Tablet

Servings Per Container

60

Best Time to Take

With meals - calcium carbonate requires stomach acid for optimal absorption and is best absorbed in doses of 500mg or less at a time

Recommended Daily Intake

Adults: 1000-1200mg elemental calcium/day; Adolescents: 1300mg/day; Postmenopausal women: 1200mg/day

Upper Tolerable Limit

2500mg elemental calcium/day for adults aged 19-50; 2000mg/day for adults over 50

Absorption Enhancers

Take with food to stimulate gastric acid secretion; adequate Vitamin D levels significantly enhance intestinal calcium absorption; Vitamin K2 directs absorbed calcium to bone

Absorption Inhibitors

High-oxalate foods (spinach, rhubarb), phytates (whole grains, legumes), excess dietary fiber, proton pump inhibitors (PPIs), H2 blockers, high-sodium diet, caffeine, and alcohol reduce absorption; iron and zinc compete for absorption - take separately

Side Effects

Possible Side Effects

Constipation, bloating, and gas are common especially at higher doses; excessive intake may cause hypercalcemia (nausea, vomiting, weakness, frequent urination, kidney stones); milk-alkali syndrome with very high doses

Upper Tolerable Limit

2500mg elemental calcium/day for adults aged 19-50; 2000mg/day for adults over 50

Safety & Warnings

Contraindications

Hypercalcemia; hypercalciuria and/or calcium-containing nephrolithiasis (kidney stones); severe renal impairment; conditions predisposing to hypercalcemia (e.g., hyperparathyroidism, sarcoidosis)

Pregnancy Safety

Consult Doctor

Breastfeeding Safety

Safe (when used at recommended doses; avoid excessive total calcium/vitamin D intake)

Children Suitability

Consult a healthcare professional for use in children under 12; adolescents 12 and above may use under medical guidance

Interactions

Medication Interactions

Reduces absorption of tetracycline and fluoroquinolone antibiotics, bisphosphonates (alendronate), levothyroxine, and iron supplements - take at least 2 hours apart; may reduce effectiveness of calcium channel blockers; thiazide diuretics increase risk of hypercalcemia when combined with high calcium intake

Supplement Interactions

Competes with iron and zinc for absorption - take separately; magnesium and calcium compete at high doses; excess calcium can impair magnesium absorption

Synergistic Nutrients

Vitamin D is crucial for calcium absorption. Magnesium and Vitamin K also work with calcium to support bone health.

Special Populations

Target Population

Postmenopausal women, elderly adults over 50, individuals with low dietary calcium intake, adolescents during peak bone mass development, pregnant and breastfeeding women, individuals with lactose intolerance avoiding dairy

Children Suitability

Consult a healthcare professional for use in children under 12; adolescents 12 and above may use under medical guidance

Pregnancy Safety

Consult Doctor

Breastfeeding Safety

Safe (when used at recommended doses; avoid excessive total calcium/vitamin D intake)

Storage & Patient Advice

SFDA Storage Conditions

store below 30°c

Storage Conditions

Store below 30°C.

Patient Counseling

Take with meals (calcium carbonate needs gastric acid for best absorption). If more calcium is needed, split doses because absorption is best at ≤500-600 mg elemental calcium per dose. Separate from levothyroxine, iron, zinc/magnesium, and certain antibiotics (tetracyclines/fluoroquinolones) by at least 2-4 hours. Ensure adequate vitamin D intake. Maintain hydration; may cause constipation and can increase kidney stone risk in susceptible patients. Do not exceed the recommended total daily elemental calcium intake from all sources (generally ≤2000-2500 mg/day depending on age).

Science & Evidence

Bioavailability Form

Calcium Carbonate - contains 40% elemental calcium by weight, the highest concentration among calcium salts; absorption is acid-dependent and optimized when taken with food

Scientific Evidence Level

Strong

Onset Timeline

Serum calcium levels normalize within days of supplementation; measurable improvements in bone mineral density require 6-12 months of consistent use

Food Sources

Dairy products (milk, cheese, yogurt), sardines and salmon with bones, tofu (calcium-set), almonds, broccoli, kale, fortified plant-based milks, sesame seeds

Product Information

Supplement Type

Mineral

Allergen Info

Contains shellfish-derived ingredient (oyster shell); individuals with shellfish allergies should consult a physician before use; free from gluten and soy

Certification

SFDA Registered (Registration No. 2610211235); GMP manufactured

Suitable for Vegetarians

Yes (oyster shell calcium carbonate is generally considered vegetarian acceptable)

Suitable for Vegans

No

Calcium Included

Yes - Calcium Carbonate from Oyster Shell 1330mg per tablet, providing 500mg elemental calcium

Vitamin K Included

No