Water Intoxication

A normal individual can drink plenty of water, which is excreted mainly in the form of the urine. The failure of excretion of water results in water intoxication (also known as over-hydration or dilution syndrome).

This occurs in case of renal failure (both acute and chronic), Addison’s disease, cirrhosis of liver, congestive heart failure, lung cancer and ovarian cancer. It may also occur within first 48 hours of a major surgery.

The retained water gets uniformly distributed in intra cellular and extra cellular spaces. As the volume of extra cellular fluid (ECF) increases, there is decreased anti-diuretic hormone (ADH) and aldosterone secretion in the body.

Symptoms of Over – hydration

The clinical presentation includes pitting oedema (that can be pitted with a finger even) and breathlessness (due to pulmonary oedema) as the main symptoms. Due to low serum sodium and osmolarity, there may be symptoms such as nausea, confusion, headache, giddiness and abdominal cramps. Rarely convulsion, coma and death may also result in as the complications. There may also be excessive salivation, lacrimation and diarrhoea (watery).

Symptoms appear very slowly after overhydration develops. In such cases, weight gain is also seen. Skin becomes warm, moist and flushed.

The first symptom seen is the swelling around the eyes, which is present when the patient wakes up in the morning. If the patient is confined to bed, he develops oedema of legs or sacral region and over the face, especially below the eyes.

Cardiac oedema is most apparent in the dependent parts and tends to disperse to other areas at night due to the change in the body position.

Treatment

Hypertonic saline infusion may be given to raise the plasma osmolarity in case of convulsion, hemiplegia or coma. Artificial dialysis may be required in case of renal failure. In mild cases, water intake may be restricted for 24 hours.