Deficiency In Serum Ionized Magnesium But Not Total Magnesium In Patients With Migraines. Possible Role Of Ica²⁺/IMg²⁺ Ratio

SYNOPSIS

It has been suggested that magnesium (Mg) may play a role in the pathogenesis of headaches. Serum and intracellular measurements of Mg in headache patients have produced inconsistent results. The recent development of an ion-selective electrode for Mg²⁺ allowed precise measurement of serum ionized magnesium (IMg²⁺) in patients with various headache syndromes. Low serum Img²⁺ and a high ICa²⁺/IMg²⁺ ratio were found in 42% of patients having an attack of migraine, but only in 23% of patients with e severe continuous headache. Total serum Mg was normal in both groups of patients. However, in patients with low serum IMg²⁺ total serum Mg was lower than in patients with normal serum IMg²⁺. These results are compatible with the serotonin and vascular concepts of migraine pathogenesis. Low IMg²⁺ and a high ICa²⁺/Img²⁺ would result in cerebral vasospasm and reduced blood flow in the brain. The activity of serotonin receptors can also be affected by changes in IMg²⁺ levels. The finding of a difference in IMg²⁺ levels in two different headache types suggests a possible novel classification of headaches and that migraine patients with a low serum IMg²⁺ or a high ICa²⁺/IMg²⁺ ratio may benefit from Mg supplementation.