Aluminum hydroxide for CRF cats--can it hurt more than it helps?

My girlfriend's cat was diagnosed with CRF a while back and she's been treating it as recommended by the vet (low-protein wet food, vitamins and aluminum hydroxide suspension to control phosphorus levels). The cat did ok for a while but recently took a turn for the worse. It refused to eat anything, even after trying every cat food on the market; after several days of this we resorted to force-feeding it by mashing up soft food and into his mouth with a syringe, but he would just vomit it up most of the time and not retain anything. The cat would just sit in the same spot all day, not moving, with its head down, not responding to touch, etc......it broke her heart. Eventually, she decided it was probably best to let the cat go; she decided to give it one or two more days where she would not force-feed or give the cat its medicine that it clearly hated to make it as comfortable as possible for their last days together. Lo and behold, the very next day, the cat started walking around again; a bit unsteady and slow, but it was moving. The next day it started nibbling at food and drinking more water. Now, the cat will eat with some regularity (although not nearly as much as it needs to; like maybe an ounce or less a day) and generally seems much happier; exploring the house, seeking attention, etc......I am wondering if the aluminum hydroxide could have been causing an allergic reaction or something with the cat? Why would simply stopping this improve the cat's condition so much? We've stopped going to the vet she started at because, for a variety of reasons, he was a jerk and didn't seem to know what he was talking about--we've had much better luck on the support groups online, and are now looking for another vet. I just was curious as to whether anyone else has had this experience with an aluminum hydroxide suspension, where it seems to do more harm than good. For now, we are just watching the cat intently and trying to make him as happy as possible; we don't want to do harm by not giving him the medicine but while on it his quality of life was terrible and he seemed listless and depressed all the time. Any help would be appreciated; thanks!