o god... now this is a worry... but i am sure this statement is enough to reasure me..
Drinking several litres over a relatively short period of time could be enough to cause water intoxication. Those most at risk include people taking ecstasy, as the drug increases thirst and facilitates the release of anti-diuretic hormones so more water is taken in but cannot be excreted. Also, elderly people because their kidney function may be impaired.