Science Cannabis

Preface to the Paperback EditionAs a scientist who works on understanding how drugs act on the brain, Iam exasperated by the way in which proponents and opponents of cannabisuse and abuse science in defending their positions. This is a drugwhose actions have been studied in some detail, including many studiesof its effects on human subjects. There is a considerable scientific literatureon how it acts and the possible adverse effects associated with its use.There have also been exciting scientific advances in the past few yearswith the discovery that the brain contains its own cannabis-like chemicalmessenger system — a finding potentially as important as the much publicizeddiscovery of morphine-like chemicals in the brain —the endorphins—in the 1970s. There have also been claims that cannabis hasimportant medical applications and these too have been researched —although less thoroughly so far.Cannabis has been demonized, however, in public debate and theavailable scientific information is largely ignored or distorted by variousgroups who use science as a propaganda weapon. In their book MarijuanaMyths and Marijuana Facts published in 1997, the authors L.Zimmer and J.P. Morgan, said that "Marijuana's therapeutic uses are welldocumented in the modern scientific literature," while in August 1996,General Barry McCaffrey, the United States drug czar bluntly said,"There is not a shred of scientific evidence that shows that smoked marijuanais useful or needed. This is not medicine. This is a cruel hoax."