Magnesium Citrate Dosage Chart
Magnesium citrate is one of the most bioavailable forms of magnesium. It is commonly used for short-term constipation relief at higher doses and as a daily supplement for magnesium sufficiency at lower doses. Its citrate salt form enhances intestinal absorption compared to magnesium oxide.
Magnesium Citrate Dosage by Age Group
| Age Group | Age Range | Dose Range | Notes |
|---|---|---|---|
| Children (6–11 yr) | 6–11 years | 100–150 mg | Under physician guidance only |
| Adolescents (12–17 yr) | 12–17 years | 200–300 mg | Split into 2 doses if needed |
| Adults — daily supplement | 18–64 years | 200–400 mg | Start at 200 mg; titrate up |
| Adults — constipation relief | 18–64 years | 1000–1750 mg | Liquid form, one-time use |
| Seniors (65+) | 65+ years | 200–350 mg | Lower dose preferred; check kidney function |
When and how to take Magnesium Citrate
Take daily supplement doses with food to reduce loose stool. For constipation, take on an empty stomach for faster onset (2–6 hours).
Available Forms
Pre-dissolved, fastest onset. Used for colon prep and acute constipation.
Contains ~1,700 mg per 10 fl oz bottle
Convenient for daily supplementation. Elemental magnesium varies by product.
Typical capsule: 100–200 mg elemental Mg
Mix with water. Cost-effective for long-term use.
Citrate powder absorbs quickly
Safety Cautions
- Do not exceed 400 mg/day for daily use without medical supervision.
- High single doses (constipation range) can cause severe diarrhea and electrolyte imbalance.
- Avoid if you have kidney disease — magnesium accumulates without proper renal clearance.
- May interact with certain antibiotics (tetracyclines, quinolones) — space by 2 hours.
- Not recommended during pregnancy without consulting a healthcare provider.
Frequently Asked Questions
How much magnesium citrate should I take for constipation?
Adults typically take one full 10 fl oz bottle (approximately 1,700 mg magnesium citrate) for constipation. Results appear within 2–6 hours. This is a one-time dose, not a daily supplement amount.
How much magnesium citrate per day is safe long-term?
The tolerable upper intake level (UL) for supplemental magnesium is 350 mg/day for adults from all non-food sources. Most people do well at 200–400 mg/day elemental magnesium from citrate.
What is the difference between magnesium citrate and magnesium glycinate?
Magnesium citrate has a mild laxative effect at higher doses and is well-absorbed. Magnesium glycinate is bound to the amino acid glycine, is gentler on digestion, and is preferred for sleep and anxiety support without laxative effects.
Can I take magnesium citrate every day?
Yes, at supplemental doses (200–400 mg elemental magnesium). Daily use at constipation doses (1,000+ mg) is not recommended — it causes dependence and electrolyte loss.
Sources & References
- NIH Office of Dietary Supplements — Magnesium Fact Sheet
- FDA drug label: Magnesium Citrate Oral Solution
- NIH Tolerable Upper Intake Levels (UL) for Magnesium