Fear and Doubt

Hello,
I don't know if anyone can help me on this one. I am plagued with fear and doubts about advising my brother to stop his chemo and to do Dr. Clark's 21 day cleanse. My heart is breaking to watch what this chemo is doing to him.
My brother has terminal colon cancer. He has been fighting cancer for two years now but his terminal diagnosis was last April. He has been on chemo for a year and half. He is on the last chemo drug known to work for his type of cancer. He started this new chemo drug over a month ago and he has taken a drastic turn for the worse. He has been basically bed ridden for weeks. He can barely eat anything. He is starting to vomit everything he eats or drinks. It's horrible. His doctor says it's most likely the cancer not the chemo. You can see the tumors pushing his bellow and bowels outward. His right side and his lower right back are swollen and hard. He is in a lot of pain and taking a lot of morphine.
The doctor told my mother that there is nothing else they can do for him. He has not told my brother this. I think my brother has a right to know what the doctor told my mother but my mother doesn't want to tell him for fear of taking away his hope.
My brother has one more week of this chemo drug left and then his doctor is cutting him lose. My brohter has been relying on the chemo drugs. They seem to give him some hope but he is wondering if he should stop taking them. He seems to think that he should finish out the next week but he is torn. So am I.
He is surely going to die soon if a miracle doesn't happen. Why bother taking these poisonous drugs if they aren't working?
I don't know what my question is really. I am just filled with fear and doubt. I don't want to tell him...."Stop the chemo Steve. Let's do Dr. Clark's treatment. She says it can work." I don't want to give him false hope, I guess.
I am so scared and confused. I don't know if anyone can help me on this forum or not.

But thank you for being here to let me vent.
God bless you all!
Pearls