Calcium Supplementation
Key Points
- Essential for bone mineralization and growth
- Critical during periods of rapid skeletal development
- Multiple formulations with varying bioavailability
- Requirements vary by age and clinical condition
- Absorption dependent on vitamin D status
Elemental Calcium Content
- Calcium carbonate: 40% elemental calcium
- Calcium citrate: 21% elemental calcium
- Calcium gluconate: 9% elemental calcium
- Calcium lactate: 13% elemental calcium
Available Formulations
Oral Preparations
- Calcium Carbonate
- Most common and cost-effective
- Requires acidic environment
- Available forms: chewable, tablets, powder
- Strengths: 250mg, 500mg, 600mg, 1250mg
- Calcium Citrate
- Better absorbed in achlorhydria
- Can be taken without food
- Available forms: tablets, powder
- Strengths: 200mg, 250mg, 500mg
- Calcium Gluconate
- Used in neonatal preparations
- Lower elemental calcium content
- Better tolerated
Injectable Preparations
- Calcium Gluconate
- 10% solution (100mg/mL)
- Preferred for IV administration
- Less irritating to veins
- Calcium Chloride
- 10% solution (100mg/mL)
- Reserved for emergency situations
- Central line administration preferred
Clinical Indications
Primary Indications
- Nutritional Deficiency
- Inadequate dietary intake
- Vegetarian/vegan diets
- Milk protein allergy
- Lactose intolerance
- Medical Conditions
- Chronic kidney disease
- Hypoparathyroidism
- Rickets
- Osteoporosis
- Malabsorption syndromes
Secondary Indications
- Growth periods
- Rapid infant growth
- Adolescent growth spurt
- Pregnancy in adolescents
- Special Situations
- Athletes with high training loads
- Eating disorders
- Post-bariatric surgery
- Chronic steroid therapy
Administration & Dosing
Daily Requirements by Age
- 0-6 months: 200mg
- 6-12 months: 260mg
- 1-3 years: 700mg
- 4-8 years: 1000mg
- 9-18 years: 1300mg
Therapeutic Dosing
- Mild Deficiency
- Additional 500mg/day
- Divided into 2-3 doses
- Moderate-Severe Deficiency
- Additional 1000-1500mg/day
- Divided into 3-4 doses
- Hypoparathyroidism
- Up to 2000-2500mg/day
- Requires careful monitoring
Administration Tips
- Timing Considerations
- Space doses 4-6 hours apart
- Avoid iron-containing supplements by 2 hours
- Take with meals (except citrate)
- Optimization Strategies
- Combine with vitamin D
- Small frequent doses preferred
- Consider patient preference for formulation
Monitoring & Assessment
Initial Evaluation
- Laboratory Assessment
- Serum calcium
- Ionized calcium
- Phosphate
- Vitamin D levels
- PTH if indicated
- Alkaline phosphatase
- Clinical Assessment
- Dietary calcium intake
- Growth parameters
- Bone pain or fractures
- Risk factors assessment
Follow-up Monitoring
- Regular Monitoring
- Serum calcium every 3-6 months
- Urinary calcium annually
- Growth velocity
- Bone density as indicated
- Compliance Assessment
- Supplement diary
- Side effects review
- Barriers to administration
Clinical Considerations
Special Populations
- Premature Infants
- Higher calcium requirements
- Need for careful monitoring
- Risk of nephrocalcinosis
- Chronic Diseases
- Modified absorption
- Drug interactions
- Comorbidity impact
Drug Interactions
- Medications Affecting Absorption
- Tetracyclines
- Fluoroquinolones
- Bisphosphonates
- Levothyroxine
- Medications Affecting Metabolism
- Anticonvulsants
- Corticosteroids
- Loop diuretics
Complications & Side Effects
Common Side Effects
- Gastrointestinal
- Constipation
- Bloating
- Nausea
- Abdominal pain
- Compliance Issues
- Taste concerns
- Pill burden
- Administration timing
Serious Complications
- Hypercalcemia
- Risk with excessive supplementation
- Monitoring required
- Symptoms: lethargy, weakness, confusion
- Kidney Complications
- Nephrolithiasis
- Nephrocalcinosis
- Risk with high-dose supplementation
Further Reading
