Oral magnesium load test in patients with migraine

Objective.-To determine whether migraineurs may, hake a systemic deficiency of magnesium. Background.-Magnesium deficiency has been shown to play a potential role in the pathogenesis of migraine, but there are no data on total body migraineurs. Methods.-An oral magnesium load test as performed by giving 3000 mg of magnesium lactate during a 24-hour interictal period to 20 patients with migraine (15 women and 5 men; mean age, 37.9 years) and 20 healthy volunteers (16 women and 4 men; mean age, 39.6 years). Baseline and postload magnesium concentrations were determined from serum and 24-hour urine specimens. Results.-There was no significant difference between the groups in the baseline serum and urine magnesium concentrations, although the latter tended to be lower (P=.064) in the migraine group. The postload magnesium concentrations were significantly, higher within both the migraine (P<.0001 and P<.0001) and the control (P=.0009 and P<.0001) groups compared to the baseline values. After loading, the 24-hour urinary, magnesium excretions were significantly lower (P=.0007) in the patients with migraine than in the controls, but serum values did not differ. Conclusions.-Magnesium retention occurs in patients with migraine after oral loading, suggesting a systemic magnesium deficiency.