Placebo-controlled, double-blind, cross-over study shows fast-acting pharmacokinetic properties of magnesium citrate after single-dose administration

摘要

Background: Due to the widespread use of magnesium (Mg) and its positive effects on human health, pharmacokinetic properties and bioavailability of Mg are of interest. This study investigates the time course of renal elimination and plasma concentration after single-dose administration of 300 mg Mg from Mg citrate. Materials and methods: 10 healthy males were supplemented with 400 mg Mg daily for 1 week to saturate Mg pools before taking the test products. After administration, urinary Mg excretion was determined between 0 and 2 hours, 2 and 4 hours, 4 and 8 hours, and 8 and 24 hours, and plasma Mg concentration at time points 0, 30, 60, 90 minutes, 2, 4, 8, and 24 hours. Results: Single-dose Mg citrate supplementation led to a significant increase in urinary Mg excretion already after 2 - 4 hours of administration (0.52 +/- 0.25 mmol) compared to placebo (0.32 +/- 0.16 mmol; p < 0.02). This effect remained significant also for urinary Mg excretion collected from 4 to 8 hours and 8 to 24 hours after supplementation. Plasma Mg concentration was significantly higher for Mg citrate compared to placebo already after 30 minutes (0.79 +/- 0.07 vs. 0.76 +/- 0.09 mmol/L; p < 0.01) as well as for measuring time points of 60 minutes (0.80 +/- 0.05 vs. 0.75 +/- 0.08 mmol/L; p < 0.01) and 90 minutes (0.81 +/- 0.05 vs. 0.77 +/- 0.07 mmol/L; p < 0.01) after administration. Conclusion: Single-dose administration of Mg given as organic Mg citrate is quickly absorbed and shows fast pharmacokinetic properties resulting in high bioavailability.