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Bioavailability of magnesium from different pharmaceutical formulations
Roswitha Siener1, Andrea Jahnen, Albrecht Hesse
1Department of Urology, University of Bonn, Sigmund-Freud-Str. 25, 53105, Bonn, Germany. Roswitha.Siener@ukb.uni-bonn.de
Urological Research
|September 24, 2010
Summary
Magnesium oxide bioavailability differs between formulations. Effervescent tablets showed better magnesium absorption than capsules, likely due to ionization before ingestion.
Area of Science:
- Nephrology
- Nutritional Science
- Pharmacology
Background:
- Magnesium may reduce intestinal oxalate absorption and inhibit calcium oxalate crystallization.
- Oral magnesium supplementation has shown limited urinary excretion increases, suggesting low bioavailability.
- Investigating magnesium oxide (MgO) bioavailability from different pharmaceutical forms is crucial.
Purpose of the Study:
- To compare the bioavailability of magnesium from MgO capsules versus MgO effervescent tablets.
- To assess the impact of formulation on urinary magnesium excretion and absorption.
Main Methods:
- A cross-over study involving 13 healthy male volunteers.
- Supplementation with 450 mg magnesium from MgO capsules and effervescent tablets under standardized dietary conditions.
- Collection of fractional urine and blood samples, with weekly 24-h urine collections during follow-up.
Main Results:
- Urinary magnesium excretion increased by 40% with effervescent tablets compared to 20% with capsules.
- This suggests significantly better magnesium bioavailability from the effervescent tablet formulation.
- Ionization of magnesium in effervescent tablets before ingestion may enhance absorption.
Conclusions:
- Magnesium bioavailability from effervescent tablets is superior to that from MgO capsules.
- The enhanced absorption is likely due to magnesium ionization facilitated by dissolving the tablets in water.
- These findings have implications for optimizing magnesium supplementation strategies.
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