Downbeat Nystagmus With Magnesium Depletion

Two patients with neurological signs of magnesium depletion complained of oscillopsia and manifested downbeat nystagmus. Serum magnesium levels measured less than 1.0 mg/dL. Hypomagnesemia resulted from debilitating intestinal disease in both patients and apparently was aggravated in one case by failure to add magnesium sulfate to the patient's regimen for total parenteral nutrition. Neither patient had any of the neurological conditions...