Science Says: What’s known and not known about marijuana
NEW YORK — A new marijuana study joins a limited record of scientific knowledge about the harms and benefits of pot.
The research published Wednesday is the first rigorous test of a marijuana compound in treating a certain form of severe epilepsy. It found that an ingredient of marijuana — one that doesn’t give pot smokers a high — reduced the number of seizures in children.
In the U.S., more than two dozen states allow medical use of marijuana. Federal drug regulators have not approved marijuana itself, but they have allowed man-made, chemically related medicines to treat loss of appetite in people with AIDS, and nausea and vomiting caused by cancer therapy. A marijuana extract is sold in Britain for nerve pain and other problems from multiple sclerosis.
In January, a U.S. advisory committee concluded that the lack of scientific information about marijuana and its chemical cousins, called cannabinoids, poses a risk to public health. The experts called for a national effort to learn more.


