# Pilot study of a topical magnesium preparation to treat hypomagnesaemia in patients with an ileostomy

## TL;DR

This pilot study tested a magnesium spray to treat low magnesium levels in ileostomy patients and found it helped maintain or increase magnesium and reduce muscle cramps.

## Contribution

The study introduces a topical magnesium chloride spray as a potential treatment for hypomagnesaemia in ileostomy patients.

## Key findings

- Three out of six patients showed improved serum magnesium levels after using the spray.
- Five patients reported reduced muscle cramping within three weeks of treatment.
- Serum and whole cell magnesium levels showed a strong linear correlation.

## Abstract

Patients with a high output ileostomy often have hypomagnesaemia. This study aimed to determine if a magnesium chloride hexahydrate spray would maintain or increase serum magnesium in ileostomy patients with hypomagnesaemia.

Outpatients with an ileostomy and having chronic hypomagnesaemia (serum magnesium <0.66 mmol/L) applied 10 sprays of magnesium chloride hexahydrate spray twice daily for 6 weeks (150 mg/day, 6.2 mmol magnesium). Serum and whole cell Mg+2 levels were measured at weeks 0, 1, 3 and 6. A treatment response was a rise in serum Mg+2 > 0.10 mmol/L at week 6, or the avoidance of a planned magnesium infusion. Serum vitamin D and aldosterone levels, and a 24-hour urinary magnesium concentration were measured.

6 patients completed the study, all had normal vitamin D levels (>45 nmol/L), and 5 of 6 had urinary magnesium concentrations below 0.28 mmol/L. 2 patients had a rise in serum Mg+2 of 0.27 and 0.13 mmol/l respectively and one avoided their planned six-weekly magnesium infusion, No patient had a fall in serum Mg+2 of more than 0.07 mmol/L. Serum and whole cell Mg+2 correlation was linear (r = 0.9181, p < 0.0001). All 6 patients complained of muscle cramping at enrolment; 5 reported an improvement or complete resolution by week 3. Serum aldosterone levels were high at the start in 4 and reduced in 3. Urine magnesium concentration increased in 2.

A topical magnesium chloride hexahydrate spray maintains or improves serum magnesium levels in patients with an ileostomy and hypomagnesaemia and prevents muscle cramps.

RD13–045