Comparison of the Effects of Magnesium Hydroxide and a Bulk Laxative on Lipids, Carbohydrates, Vitamins A and E, and Minerals in Geriatric Hospital Patients in the Treatment of Constipation

Abstract

In a crossover study the effects of magnesium hydroxide on serum lipids, carbohydrates, vitamins A and E, uric acid and whole blood minerals were compared with those of a bulk laxative containing plantago rind and sorbitol in 64 constipated, elderly long-stay patients, 55 of whom were receiving diuretics. Hypomagnesaemia occurred in 11 (17%) patients after bulk laxative and in two (2%) patients after magnesium hydroxide treatment. There was a slight reduction in low values of high-density lipoprotein cholesterol and high values of triglycerides after magnesium hydroxide treatment. There were no significant differences in plasma lipids, whole blood minerals or vitamins A and E using either laxative. Negative correlations were found between the increase in serum concentrations of magnesium and glycosylated haemoglobin A1 (P less than 0.02) and the serum level of uric acid (P less than 0.01). These results suggest that the long-term effects of magnesium hydroxide and bulk laxative on the absorption of nutrients may not be significantly different. Magnesium hydroxide, however, may have beneficial effects on lipid disorders, impaired glucose tolerance and hyperuricaemia in magnesium deficiency due to diuretics and thus may be a favourable laxative for use in bedridden geriatric patients receiving diuretics.

Mild dehydration: a risk factor of constipation?

“…For the treatment of impaction with saline laxatives (Kamm & Speakman, 1993), the active ingredients, magnesium hydroxide (Kinnunen & Salokannel, 1989) or magnesium sulphate (Epsom salts), phosphate and citrate ions are relatively fast acting (American College of Gastroenterology's Committee, 1985). Laxatives have been generally classified according to their chemical properties rather than their mechanisms by which they increase stool water (Fingl, 1983).…”

Constipation in the Elderly

“…There is a risk of impaction with bulk laxatives, as with high fiber, in elderly people who do not drink sufficiently, though there are no published reports of this complication. Bulk laxatives do not cause malabsorption of iron (unlike unprocessed bran), fat‐soluble vitamins, or digoxin in elderly users 120,121 …”

“…The risk of side‐effects increases with higher potency salts such as magnesium citrate, which is a commonly prescribed agent despite the absence of any clinical study on its use as a laxative. Magnesium levels should be monitored periodically in all elderly people who are using these agents chronically, since hypermagnesemia can occur even with normal serum creatinine levels, 61 and long‐term use is contraindicated in moderate renal insufficiency 97,120 . There is one published study on the benefits of saline laxatives in elderly people 98 .…”

Aktualisierte S2k-Leitlinie chronische Obstipation der Deutschen Gesellschaft für Gastroenterologie, Verdauungs- und Stoffwechselkrankheiten (DGVS) und der Deutschen Gesellschaft für Neurogastroenterologie & Motilität (DGNM) – April 2022 – AWMF-Registriernummer: 021–019

“…Auch die Anthrachinone haben eine duale Wirkungsweise (prokinetisch und sekretagog) 230 231 232 . Ihre Wirksamkeit bei kurzfristiger und mehrwöchiger Gabe sowie ihre Überlegenheit gegenüber Lactulose wurden in kontrollierten Studien nachgewiesen 137 233 234 235 236 237 238 . Elektrolytverschiebungen im Serum wurden dabei nicht beobachtet 239 240 .…”