Moduretic-induced metabolic acidosis and hyperkalaemia

Area of Science:

• Nephrology
• Clinical Pharmacology

Background:

• Moduretic, a combination diuretic containing amiloride and hydrochlorothiazide, is commonly prescribed for hypertension and edema.
• Electrolyte disturbances, including hyperkalemia and metabolic acidosis, are known potential side effects of potassium-sparing diuretics like amiloride.

Observation:

• A case study details a patient who developed significant metabolic acidosis and severe hyperkalemia (peak potassium 7.6 mmol/l) during Moduretic treatment.
• Despite severe hyperkalemia, the patient's total body potassium levels remained normal throughout the observation period.

Findings:

• Discontinuation of Moduretic led to the normalization of the patient's acid-base balance and serum potassium levels within approximately 10 days.
• The findings suggest a direct causal relationship between Moduretic use and the observed metabolic disturbances.

Implications:

• This case highlights the importance of monitoring electrolytes and acid-base balance in patients taking Moduretic, especially those with risk factors for hyperkalemia.
• Further investigation into the specific mechanisms by which amiloride and hydrochlorothiazide contribute to metabolic acidosis and hyperkalemia in certain patients is warranted.