Adverse reaction to anti-nausea medicine and phosphorus binders

My cat has CRF, and is now in quite an advanced stage of the disease. He doesn't eat anything besides the liquids we feed him- made of cooked egg yolk or fish stock. To get him to eat more we've tried two different anti-nausea medications- domperidone and ondansentron to be specific. He reacts in the same way to each- throws up the clear froth that is supposedly a sign of excess acids in the stomach. He does this immediately after the medicines. And he also threw up after frothing today. Does anyone know why he reacts to these anti-nausea meds this way?

He has an extremely high phosphorus count. Are cats with kidney problems put on phosphorus binders? Which ones are generally used?

Thank you very much.

For your questions, I am going to refer you to the website that was referenced in your other thread, but this time to a different "page" of the website.  This one addresses both of your issues. http://www.felinecrf.org/phosphorus.htm#control_binders

  I just hope you will be able to locate the phosphorus binders where you are located.  The eggshell powder Carolina referenced in your other thread will work to some degree as a phos binder (example:  to offset the phos in the egg yolk), but if his phosphorus overall is extremely high, then you'll do better with an aluminum hydroxel binder. 

Also, from this page of that website:  http://www.felinecrf.org/tanyas_support_group.htm, you can click on the link to join the yahoo support group that is comprised of all people who have kidney cats and there is someone available (it seems like) 24 hours a day answering questions from people all over the world.  If you need a quick answer, or need to know how to use a product, etc. there is usually someone who has tried it, etc. who can get back to you quickly.  It certainly can't hurt to join. 

My vet had us use Epakitin for phosphate binder for my CRF cat. You can ask your vet if this is appropriate for your cat.
We also were given Azodyl which is a probiotic supplement to support the kidneys.

I am using aluminum hydroxide powder which I mix into my cat's food. There is also Alugel which is an oral liquid. In terms of crf in general, ask your doctor about benazapril-some vets will prescribe it as soon as a cat is diagnosed with crf-helps the kidneys filter better. There's also Calcitriol-something to do with parathyroidism- I can't recall the specifics but it is related somehow to crf. Your doctor will have to check your cat's ionized calcium first however. Adding omega 3 fatty acids is also helpful.