Depends on if your body is dehydrated or not. If your heavily reliant on them it may take a while for your body to adjust- just how long will likely be tied to your age, your weight/size, any underlying conditions and genetics.
If you are heavily dependant on them I'd seek medical advice as to why and how you can cut down if its causing your health problems but yes, you will lose weight when taking them, but its just water weight not fat loss and it can put your heart at risk through electrolyte inbalances so its a good idea to get things checked out to makes sure your fit and healthy.