Dear Doctor - Seeking medications for cat with kidney disease
[From Tufts August 2011 Issue]
Our cat, Jill, needs fluids because she is in kidney failure. We’ve been hydrating her for years, and she seems to be responding well. Her kidney values appear fairly stable.
Lately, we’ve noticed that she throws up almost every time after we give her the fluids. She throws up quite frequently even when not being hydrated, but not with such regularity. Every morning we have been giving her metoclopramide for nausea. Our veterinarian does not understand why Jill throws up after hydration. She suggested giving the metoclopramide in the afternoon, prior to hydration, but this change in the schedule hasn’t helped. Any advice you could give us would be greatly appreciated.
Judy and Pedro Hecht
Dear Judy and Pedro: As a feline practitioner, I treat many cats with chronic renal failure. Most of my patients do not require subcutaneous fluids at home, but a few who have trouble maintaining adequate hydration do benefit from this type of additional fluid support. I’ve never had any client report vomiting right after hydration, and I can’t come up with a reason why it might be happening. As you noted, vomiting is a common sign in cats with chronic renal failure in general.
The kidneys’ job is to filter toxins from the bloodstream. One of the substances that the kidneys filter is a hormone called gastrin. Gastrin causes the stomach to secrete acid. As kidney function progressively declines, the gastrin level in the bloodstream begins to rise. High levels of gastrin result in high levels of gastric acid which, in turn, can lead to nausea, vomiting and poor appetite.
Metoclopramide is a good anti-vomiting drug, but it doesn’t address the issue of stomach acid as a cause of the vomiting. You might want to consider an antacid instead of (or in addition to) the metoclopramide. An excellent choice would be famotidine (Pepcid). A quarter of a 10-milligram tablet once a day is the typical dose that I use.
There are many other disorders that can cause vomiting in cats, for example, pancreatitis and inflammatory bowel disease. We shouldn’t have tunnel vision and assume that your cat’s vomiting is 100-percent due to the renal disease. If acid-reducing drugs do not help, other anti-vomiting drugs can be prescribed, but I would have your cat evaluated for other possible causes of vomiting if the vomiting persists and is refractory to medication.
Arnold Plotnick, DVM