Here is my answer to him, and now I hope that future internet searchers for this topic will find this post where all the BCG process, expectations, and my experience are consolidated.
The BCG instillation procedure should not be painful. The key is to relax. Relaxing is quite difficult the first time a stranger puts a tube up inside your bladder. The key is to take slow deep breaths through your mouth and do not hold your breath, which is the natural reaction! Holding the BCG in the bladder should not be difficult - they only put in 50 ml, and you don't feel much - maybe a small burning. If you drink enough fluids, getting through the 8 hours afterwards is easier. Most people do not have side effects on the 1st BCG. I was told not to drink any fluids at all for at least four hours before BCG. After putting BCG in, hold for 2 hours. Then for next six hours, use bleach in toilet. I avoided all fluids for 10 hours before, except brushing my teeth. I had a lot of things prepared in advance to make it easier. Preparations (which may be a little on the overkill side) are described HERE.UPDATE: As of October, 2011, I have completed exactly half of my BCG maintenance treatments. Please refer to my BCG lessons learned HERE.
THIS POST describes in detail what I did to deal with handling requirements for the first few BCG treatments:
For instillation a catheter will be inserted - takes about 20-30 seconds. Then 30 seconds to put in the BCG solution. 10 seconds to remove tube - they will not leave it in like a Foley. Having the tube put in is for my first six treatments is described at the top of this page - do keep in mind that they use a smaller tube with no balloon for BCG instillations, and they don't leave the tube in - thank goodness!
My six initial BCG inputs are described, and my particular side effects listed in great detail at the bottom of the page here.
What most folks experience might be slightly worse than my symptoms, and that's described HERE.
A much more unpleasant set of side effects happened to a man in England. There is no way to predict how any one person will react to BCG. Does not matter what your age is, your gender, your cancer grade or stage, or where you live. The more serious side effects that can occur are described here. Hopefully yours will be more like mine than his. In my opinion he did not drink enough fluids.
My fluid regimen is to drink 16 ounces (half a liter) slowly over the first hour (immediately after BCG), 16 more ounces the next half hour, and then 32 ounces (1 liter) the next half hour immediately before voiding the BCG. This has made getting the BCG out after 2 hours much easier, and hasn't created any "holding problems." Then I continue with 32 ounces or more per hour for the next six hours, then cut to half of that for the balance of the evening. This schedule keeps me going most of the night at least hourly, but the volume has purged the BCG, blood, and clots very well. Keep in mind that the instructions say no fluids for 4 hours before. I drink a little regular water, but major hydration is done with water, room temperature iced tea, and spicy lemonade. If you need flavoring in the water, use organic lemon, lime, or orange juice. If you need sweetener with that or the iced tea, use stevia, a natural leaf extract. Avoid sugar and high fructose corn syrup, which cause glucose spikes in the bloodstream - glucose is cancer's favorite food. And avoid artificial sweeteners, which MAY stimulate cancer triggers in your system - even though not proven, why take a chance? And everyone tells you not to drink tea to hydrate because it is a diuretic (makes you pee). I'm no expert, but what could be better in this absurd situation? Perhaps one thing - if you are not taking any medications that preclude it, beer and wine are also acceptable!
Best advice for prospective BCG recipients: RELAX, DEEP SLOW BREATHING, DRINK MUCH FLUID FOR FULL 8 HOURS!
Best of success to you.