How much Requip is too Much?

My 80 yr. old father-in-law has been taking 0.125 mg of requip for a couple of years. The shaking in his hand is still there, so he went to see a neurologist and he has QUADRUPLED his dose.
My father-in-law has been on this new dose a month and still has the shakes as bad as he did.
The cost of this medication is a major drain, it is so expensive and we see no benefit. We want to tell the doctor to take him off it (grandpa won't make a move without the doctor's okay).
Does anyone have any experience with this medication?