The Effect of Omeprazole on Urinary Magnesium Excretion in Children with Peptic Diseases.

Objective: This study investigates the impact of omeprazole on urinary magnesium (Mg) excretion in children undergoing treatment for peptic disease. Specifically, it examines how omeprazole influences the fractional excretion of Mg.

Methods: This single-arm clinical trial was conducted from 2020 to 2021. With 44 children diagnosed with acid peptic disease who received omeprazole (1-2 mg/kg/day) for 3 months at the Gastroenterology Clinic of Imam Hossein Hospital, Isfahan, Iran. Serum and urine levels of Mg and creatinine were measured before and after the intervention using the Pars Azmoon Kit, following the kits guidelines. The fractional excretion of Mg was then calculated using standard formulas.

Findings: The mean urinary Mg levels decreased significantly from 4.96 ± 2.48 mg/dL before treatment to 1.46 ± 0.63 mg/dL after treatment (P < 0.001). Serum Mg levels also significantly declined from 1.90 ± 0.20 mg/dL before treatment to 1.37 ± 0.03 mg/dL after treatment (P < 0.01). The mean fractional excretion of Mg decreased from 5.2% ± 1.2% before therapy to 1.7% ± 0.63% after treatment (P < 0.01). Serum creatinine levels showed a slight increase from 0.62 ± 0.19 mg/dL to 0.67 ± 0.13 mg/dL (P = 0.053), whereas urinary creatinine levels increased by 20.80 ± 18.77 mg/dL (P < 0.001).

Conclusion: The observed hypomagnesemia is not attributable to increased urinary Mg loss. Instead, the kidneys appear to compensate for the reduced serum Mg levels by decreasing urinary Mg excretion, thereby conserving Mg in the body following omeprazole treatment.