With all the meds I am on, it is not unusual for my doctor to admonish me for not drinking enough water. (They all require me to be hydrated for their optimal performance.) Generally, I drink about 3 or 4 liters a day- but I also add flavoring to some of the water, since I find it boring to drink plain water. (No fizz, just flavoring. Fizz can negate the benefits of water for hydration.)