Doctor advise to drink a litre of water first thing in morning.I do that but now pass pee every hour.Help l?

A litre all at once is quite a LOT.... but if you dehydrate fast, maybe that is why he wants you to drink so much at one time.. it is definitely not good to be dehydrated... I on the other hand have the OPPOSITE problem.... I retain water due to a heart and lung condition and must LIMIT my liquid intake to 2 litres a DAY spread out over the entire day----it really isn't very much liquid but I have to measure it carefully.... I think I'd be happier HAVING to drink a LOT then HAVING to drink too little. Oh and talk about having to PEE???? I am on a VERY STRONG dose of diruetics due also to my heart condition and everything that goes IN comes out---rather soon after drinking it too... I spend probably HALF my day in the bathroom any more... (due to my condition and the fact that I AM over 50).....