Still thirsty

Hi,

I am drinking 64 ounces a day of water but I'm still thirsty and have continuous dry mouth.

Is this normal, and will it always be like this?

64 ounces is the minimum requirement.  I have to drink 120 ounces daily or I have dry mouth, constipation and leg cramps.  Everyone is different.  You will have to experiment to find your "happy place" where fluids are concerned.  I have a water bottle with me wherever I go.