Don't drink much prior to the BCG (since you are supposed to hold it for 2 hours). If you can't make it the full 2 hours, just hold it as long as you can. After the 2 hours, drink more water than you normally do to flush your system. Best wishes and let us know how it goes.
This is my first message as it took us a second opinion to get the CIS diagnosis . My husband starts BCG this week and I would appreciate any tips on how best to tolerate the procedure . Thanks this forum is wonderful!