Dog food additive may reduce pain in cancer patients

A preservative commonly added to dog food could play a key role in reducing pain and other side-effects in cancer patients undergoing chemotherapy.

According to experts at Johns Hopkins University School of Medicine in Baltimore, Maryland, an antioxidant called ethoxyquin may prevent the painful nerve damage found in the hands and feet of the majority of cancer patients who take the chemotherapy drug Taxol.

In experiments, the chemical was found to bind to certain cell proteins in a way that limits their exposure to the damaging effects of Taxol.

Researchers now intend to build on the protective effect of ethoxyquin's chemistry and develop a drug that could be administered to cancer patients before taking Taxol, similar to how anti-nausea medication is given to prevent the nausea that often accompanies chemotherapy.

Although half of Taxol users eventually recover from the pain damage, which is known as peripheral neuropathy, the other half continue to have often debilitating pain, numbness and tingling for the rest of their lives, explained Dr Ahmet Hoke, a professor of neurology and neuroscience at Johns Hopkins and director of the Neuromuscular Division.

"Millions of people with breast cancer, ovarian cancer and other solid tumors get Taxol to treat their cancer and 80 per cent of them will get peripheral neuropathy as a result. 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," he added.

Dr Hoke and his team now intend to determine whether the medication could also make nerves more resistant to damage in peripheral neuropathy caused by other major causes of pain, such as HIV and diabetes.

Past research has already suggested that ataxin-2 could cause degeneration in motor neurons in Lou Gehrig's disease, which suggests that ethoxyquin or a variant may also benefit people with the condition.