The benefits of cannabis for patients on chemotherapy have long been known. A Harvard study from the mid 1990s, before any states had legalized medical use, found that nearly half of all oncologists recommended cannabis to their patients. Cannabis may help prevent nausea in certain situations -- relief  many cancer chemotherapy patients can't obtain from existing drugs, says a University of Guelph psychology professor, Linda Parker. Her research was published in recent issues of the journal Physiology and Behavior.

Many chemotherapy patients vomit walking into clinics in anticipation of treatment. The symptoms can deter some patients from continuing with recommended treatment, said Parker, a behaviour neuroscientist. "Known antiemetic drugs aren't effective in treating this learned nausea," she said. Medication can control vomiting in 60 to 70 per cent of chemotherapy patients, but many still suffer from nausea.

Using rats and shrews, Parker has been able to determine how two compounds found in cannabis -- THC (the chemical that makes people feel high) and cannabidiol (CBD) -- can treat vomiting and nausea. "People report that if they smoke marijuana before they go for chemotherapy treatment, they don't experience the anticipatory nausea or vomiting," Parker says. She's been collaborating with THC discoverer, Raphael Mechoulam, at the Hebrew University in Jerusalem.

Mechoulam also discovered the natural chemical in the body that acts on the same brain receptor (cannabinoid receptors) responsible for cannabis making people high - the equivalent of endorphins for morphine. It's called anandamide, known as "the brain's own THC," and Parker is looking at the role it plays in nausea and vomiting.

Source: Canada Network, Windsor Star (Canada), August 24th, 2006
http://www.canada.com/windsorstar/news/body_health/story.html?id=c237886d-5c69-4e98-8f74-cc8724023d4c