Magnesium-Potassium Complex, 250 Capsules
Douglas Labs' Magnesium-Potassium Complex combines two essential electrolyte minerals in a single formula designed to support muscle function, cardiovascular health, and fluid balance.
May be a fit for
- Adults seeking combined magnesium and potassium support for muscle function
- Individuals maintaining electrolyte balance during high physical activity
- Those supporting healthy cardiovascular rhythm with magnesium-potassium complex
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Douglas Labs' Magnesium-Potassium Complex combines two essential electrolyte minerals in a single formula designed to support muscle function, cardiovascular health, and fluid balance. This practitioner-grade supplement provides magnesium and potassium in complementary forms intended to support cellular energy metabolism and electrolyte homeostasis.
Why It's Worth Considering: Douglas Labs is a long-standing name in clinical nutrition, and this combination formula addresses the frequent co-depletion of both minerals, particularly relevant for active individuals or those with higher physiological demands.
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Product details
Who it may suit
May be a fit for
- Adults seeking combined magnesium and potassium support for muscle function
- Individuals maintaining electrolyte balance during high physical activity
- Those supporting healthy cardiovascular rhythm with magnesium-potassium complex
- Practitioners protocols requiring dual-mineral repletion in a single formula
Considerations
- Severe kidney disease (impaired Mg excretion)
- Taking antibiotics — separate by 2+ hours
- Myasthenia gravis
- Already taking high-dose magnesium from another source
Compatibility & interactions
Works Well With
Take Separately From
What to expect over time
Sleep Improvement
Faster sleep onset, deeper REM
Cramp Relief
Reduced nighttime cramps and muscle tension
Mood & Calm
Lower baseline anxiety, improved stress resilience
Serum Optimization
Measurable RBC magnesium improvement
Based on clinical research on magnesium supplementation. Effects are cumulative with consistent daily use.
Compare the options
Compare Magnesium Forms
Which form is right for you?
| Feature | Glycinate | Citrate | Oxide | L-Threonate | Taurate |
|---|---|---|---|---|---|
| Bioavailability | High (chelated) | Moderate-High | Low (4-5%) | Moderate | Moderate-High |
| Best For | Sleep, anxiety, cramps | Constipation, general | Budget (low absorption) | Cognitive function | Heart health |
| GI Tolerance | Excellent | Moderate | Poor (laxative) | Good | Good |
| Laxative Effect | None | Mild–Moderate | Strong | None | None |
| Evidence | Strong | Strong | Weak | Emerging | Moderate |
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462 product and brand ratings and mentions across 4 sources.
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Explore the source sentiment summary
Overwhelmingly positive consensus on magnesium supplementation for sleep, energy, and mood, with high bioavailability praised across sources.
This summary includes broader brand discussion. Individual experiences are not evidence of product effectiveness.
A few useful answers.
Research & further reading
More category questions
What is the best form of magnesium to take?
Magnesium glycinate (bisglycinate chelate) is widely considered the best form for sleep, anxiety, and muscle cramps due to high bioavailability and zero laxative effect. Citrate is better for constipation. Threonate may be superior for cognitive function as it crosses the blood-brain barrier. Oxide has only 4-5% absorption and is primarily a laxative.
Does magnesium glycinate cause diarrhea?
No. Unlike magnesium citrate and oxide which draw water into the intestines (osmotic laxative effect), glycinate is chelated and absorbed through a different pathway that does not affect GI motility. It is the most GI-friendly magnesium form available.
When is the best time to take magnesium?
Take 1-2 hours before bed for sleep benefits. The glycine component promotes relaxation via GABA receptor activity. For general supplementation, any time works — glycinate does not require food for absorption.
How do I know if I am magnesium deficient?
Standard blood tests (serum magnesium) are unreliable — only 1% of body magnesium is in the blood. Signs include muscle cramps, poor sleep, anxiety, eye twitches, chocolate cravings, and headaches. Since 80%+ of adults are suboptimal, supplementation is generally recommended.
Can I take magnesium with other supplements?
Yes, but separate from zinc, calcium, and iron by 2+ hours (they compete for absorption). Magnesium pairs well with Vitamin D3, K2, and B6 taken together.
How much magnesium should I take daily?
The RDA is 310-420mg/day for adults. Most functional medicine practitioners recommend 400-600mg for therapeutic benefit. Start with the product's recommended dose and adjust based on response.
Supplement information is provided for education and is not a substitute for personalized medical advice. Supplements are not intended to diagnose, treat, cure or prevent disease. Read the current product label before use.