Too much water – whatever amount the kidneys are unable to excrete – can be toxic, but an excessive amount would have to approach many liters each day. Most people have little risk of drinking too much water, but problems do accompany some disease states and mental disorders. When water exceeds the kidney’s capacity to excrete, blurred vision is one resulting symptom.
Water Intoxication Water intoxication occurs when there is too much fluid in the body. Excess fluid may collect in body tissues, particularly in the feet and legs resulting in a condition called oedema. Excess consumption of fluids, as well as kidney disorders that reduce urine output, may contribute to water intoxication. The symptoms of water intoxication are confusion, convulsions, and, in extreme cases, death.
Dehydration Dehydration of the body results when water is not taken in adequate amounts to make up the water loss. Dehydration occurs rapidly in severe diarrhea and vomiting in infants and children. Some clinical signs of dehydration include dry skin, less frequent urination, fatigue, light-headedness, dark-colored urine, dry mouth, and lack of skin elasticity. Often, increased fluid intake and replacement of lost electrolytes are sufficient oral rehydration therapy for mild dehydration. In cases of severe dehydration, it may be necessary to hospitalize the person and restore fluid balance through intravenous fluid replacement.