Intracellular free magnesium in lymphocytes from patients with congestive cardiac failure treated with loop diuretics with and without amiloride.

Cellular Mg2+ depletion has been reported in patients on long term diuretic therapy. We therefore measured lymphocyte free Mg2+ concentrations in patients with congestive cardiac failure treated with loop diuretics or a frusemide/amiloride mixture (Frumil) and compared them with control subjects. There was no correlation between lymphocyte free Mg2+ levels and plasma Mg2+ concentrations. Patients treated with loop diuretics did not show lymphocyte intracellular free Mg2+ depletion compared with normal controls, and those on Frumil showed higher intracellular free Mg2+ levels than normal.