Urea and Na

Q: Oral Urea tablets can be used in the treatment of? - select one

A) Hypernatremia

B) Hyponatremia

Answer: B

Although not widely used because of other modalities for treating hyponatremia, oral urea is one option for lowering sodium concentration. It is particularly useful in patients who require long-term treatment with Syndrome of Inappropriate Antidiuretic Hormone secretion (SIADH). It is popularly known as 'poor man's Vaptan.' It has shown its efficacy in acute cases also, such as on Intracranial Pressure (ICP) in Patients With Acute Brain Injury and Hyponatremia (reference# 4)

Urea is available as oral packets in the USA and can also be given via a nasogastric tube (NGT). The mechanism of action is via increasing the excretion of electrolyte-free water. The usual maintenance dose is 15 to 30 g/day.

#electrolytes

References:

1. Spasovski G, Vanholder R, Allolio B, et al. Clinical practice guideline on diagnosis and treatment of hyponatraemia. Nephrol Dial Transplant 2014; 29 Suppl 2:i1.

2. Decaux G, Andres C, Gankam Kengne F, Soupart A. Treatment of euvolemic hyponatremia in the intensive care unit by urea. Crit Care 2010; 14:R184.

3. Soupart A, Coffernils M, Couturier B, et al. Efficacy and tolerance of urea compared with vaptans for long-term treatment of patients with SIADH. Clin J Am Soc Nephrol 2012; 7:742.

4. Annoni F, Fontana V, Brimioulle S, et al. Early Effects of Enteral Urea on Intracranial Pressure in Patients With Acute Brain Injury and Hyponatremia. J Neurosurg Anesthesiol 2016.