Pubdate: Fri, 06 Jun 2014 Source: Tampa Bay Times (FL) Copyright: 2014 St. Petersburg Times Contact: http://www.sptimes.com/letters/ Website: http://www.tampabay.com/ Details: http://www.mapinc.org/media/419 Note: Named the St. Petersburg Times from 1884-2011. Author: Stephen Nohlgren, Times Staff Writer Page: 1B EXPERT: POT USE CAN BE HARMFUL Marijuana's Negatives Can Include Brain Changes And IQ Loss, A Top Drug Official Says. As Floridians consider whether to legalize medical marijuana, stories of potential benefits to patients abound. Chemicals found in pot clearly can alter important physiological mechanisms. What's less clear is risk. Pretty much any FDAA-approved medicine carries measurable risk - witness scary disclaimers in pharmaceutical ads. But marijuana comes in strains with widely different chemical contents. Users can puff it, or eat it. They can imbibe heavily or lightly. Controlled, scientific studies weighing benefits against risks don't exist. Amid the uncertainty, one of the nation's top drug officials has enlivened the marijuana debate by declaring in a prestigious publication that pot can be harmful. In a review published Wednesday in the New England Journal of Medicine , Nora Volkow, director of the National Institute on Drug Abuse, outlines marijuana's negatives, based on her reading of the medical literature. Short-term use can impair memory and learning, create temporary psychosis if taken in high doses and cause more driving accidents, Volkow states. Longterm use - particularly among those who start young - can increase the chance of permanent brain changes, addictive behavior, mental illness and loss of IQ. 'The popular notion seems to be that marijuana is a harmless pleasure," Volkow writes. But as policy shifts toward medical marijuana and legal recreational use, 'so will the number of persons for whom there will be negative health consequences." Critics of Florida's Amendment 2, which would write medical marijuana into the state Constitution, hailed the review as an important warning signal leading up to the Nov. 4 vote. 'The research showing the harms of marijuana use continues to pile up," said Calvina Fay, executive director of St. Petersburg's Save Our Society from Drugs. 'Some of these harms are so dramatic that they cannot be ignored any longer." If voters read the Volkow report and study the amendment's full language, Fay said, they 'will see that this proposed constitutional amendment is not in the best interest of the families and communities of this great state." United for Care, the amendment's sponsor, has never argued that marijuana is benign, said executive director Ben Pollara. 'We're just saying it is certainly not a horribly dangerous substance. We're just saying it should be available to really sick people as a tool in their regular medical treatment, if that is what their doctor recommends.' People do not die from too much pot, Pollara said. 'Look at that versus Advil and Tylenol, which we take on a regular basis and kills 10,000 people a year," referring to studies on the risks of those and other non-steroidal anti-inflammatory drugs. Mason Tvert, spokesman for the Marijuana Policy Project, an advocacy group, criticized NIDA 'for prioritizing politics over science.' The IQ study has been discredited, he said. As for addiction, he said, studies have indicated that pot withdrawal is no worse than getting off caffeine. Particularly troubling aspects of Volkow's review involved young people who start using pot early, and smoke heavily. Still-developing brains are more vulnerable to long-term exposure. Several studies indicate that youngsters who smoke a lot have fewer connections between brain cells. NIDA did not respond to a Tampa Bay Times request for data supporting that statement. - --- MAP posted-by: Jay Bergstrom