Excessive administration of sodium salts may cause electrolyte imbalances. Hypernatraemia is usually associated with inadequate water intake, or excessive water losses. It rarely occurs with therapeutic doses of sodium chloride. The most serious effect of hypernatraemia is dehydration of the brain which causes somnolence and confusion progressing to convulsions, coma, respiratory failure, and death. Other symptoms include thirst, reduced salivation and lachrymation, fever, sweating, tachycardia, hypertension or hypotension, headache, dizziness, restlessness, irritability, weakness, and muscular twitching and rigidity. Gastro-intestinal effects associated with acute oral ingestion of sodium chloride include nausea, vomiting, diarrhea, and abdominal cramps. Excessive administration of chloride salts may cause a loss of bicarbonate with an acidifying effect.