July 9, 1998, Washington, D.C.:
Research published in this week’s Proceedings of the National Academy of Sciences demonstrates that naturally occurring compounds in marijuana may protect brain cells during a stroke.

Researchers at the National Institute for Mental Health found that THC, the chief psychoactive compound in marijuana, and cannabidiol (CBD), a nonpsychoactive component that previously showed promise as an anti-convulsant, both appear to be potent antioxidants in laboratory studies. Doctors rely on antioxidants to protect stroke victims from exposure to toxic levels of a brain chemical called glutamate. Head trauma and strokes cause the release of excessive glutamate, often resulting in irreversible damage to brain cells.

Scientists asserted that CBD could hold advantages over other antioxidants because the compound is fast acting and nontoxic. "We have something that passes the brain barrier easily, has low toxicity, and appears to be working in animal trials," lead researcher Aidan Hampson said. "I think we have a good chance" to help patients with this compound.

The U.S. study follows earlier research conducted in Israel demonstrating that Dexanabinol—a synthetic analog derived from marijuana—protects healthy brain cells against glutamate. Israeli researchers declared this May that the drug will undergo Phase III human trials shortly. They hope to begin marketing the drug by the year 2000.

Allen St. Pierre, Executive Director of The NORML Foundation, said that the new research strengthens the need for medical marijuana reform. "This research highlights the therapeutic value of compounds in marijuana besides THC," he said. "Patients find maximum relief from whole smoked marijuana because the plant contains several therapeutic properties unavailable elsewhere. Federal law must change to allow patients access to these naturally occurring compounds."

Federal law currently prohibits the medical use of marijuana and all the plant’s active compounds other than synthetic THC.

Harvard Medical School professor Lester Grinspoon said this research represented the "tip of the iceberg" as far as the medical potential of the marijuana plant. "When science gets serious about investigating cannabis as a medicine, we will discover many more such findings," he said. Grinspoon also stressed that the scientific community has come full circle regarding marijuana’s effects on the brain.

"The debate has moved from alleging that marijuana destroys brain cells to finding that cannabis is clearly neurotherapeutic," he said.

The findings indicate that marijuana may also hold medical value in the treatment of brain diseases such as Alzheimer’s and Parkinson’s, the team of U.S. scientists said.