Dog Food Additive May Stop Painful Chemotherapy Drug Side Effects

A chemical commonly used as an additive in dog food may be able to prevent the kind of painful nerve damage commonly found in the hands and feet of cancer patients taking the chemotherapy drug Taxol.

The antioxidant ethoxyquin, which is used as an FDA-approved preservative in dog food, has been shown to bind to certain proteins in a way that limits exposure to the damaging effects of Taxol.

"Millions of people with breast cancer, ovarian cancer and other solid tumors get Taxol to treat their cancer and 80 percent of them will get peripheral neuropathy as a result," said Dr. Ahmet Höke, a professor of neurology and neuroscience at the Johns Hopkins University School of Medicine.

Höke and his colleagues published their research is published in the journal Annals of Neurology.

"They're living longer thanks to the chemotherapy, but they are often miserable. Our goal is to prevent them from getting neuropathy in the first place," Höke said, referring to the pain damage that comes as a side effect of Taxol. Half of Taxol users recover from the pain damage, but the other half continue to have debilitating pain, numbness and tingling for the rest of their lives.

Previous experiments led Höke and his team to knew that adding Taxol to nerve cell lining would cause neurodegeneration. Their latest research sought to find compounds that might interrupt the degenerative process.

The team tested more than 2,000 compounds - one at a time - to see if any could do so, finding that ethoxyquin could make cells resistant to the taxing effects of Taxol.

If further tests prove successful, a new treatment for peripheral neuropathy could be developed, which Höke says could be a boon for cancer patients.

Höke said 20 to 30 million Americans suffer from peripheral neuropathy.

It's a "huge public health issue" that doesn't get much attention because it is not fatal, Höke said.