Abstract

We report six cases of hyponatraemia secondary to heart failure and cirrhosis that were corrected after oral administration of crystallised urea (30 g/day in all patients). A marked clinical improvement was observed after <7 days of treatment, with good metabolic control, disappearance of oedema and recovery of plasma sodium levels; the treatment was well tolerated, and there were no major adverse effects. All patients continued to receive furosemide perfusion during their urea treatment, and no fluid restrictions were imposed. Oral urea offers a safe, effective and inexpensive treatment for hyponatraemia associated with heart failure and cirrhosis.