LOS ANGELES — Propelled by an increase in prescription narcotic overdoses, drug deaths now outnumber traffic fatalities in the United States, a Los Angeles Times analysis of government data has found.Drugs exceeded motor vehicle accidents as a cause of death in 2009, killing at least 37,485 people nationwide, according to preliminary data from the U.S. Centers for Disease Control and Prevention.While most major causes of preventable death are declining, drugs are an exception. The death toll has doubled in the last decade, now claiming a life every 14 minutes. By contrast, traffic accidents have been dropping for decades because of huge investments in auto safety.Public health experts have used the comparison to draw attention to the nation’s growing prescription drug problem, which they characterize as an epidemic. This is the first time that drugs have accounted for more fatalities than traffic accidents since the government started tracking drug-induced deaths in 1979.Fueling the surge in deaths are prescription pain and anxiety drugs that are potent, highly addictive and especially dangerous when combined with one another or with other drugs or alcohol. Among the most commonly abused are OxyContin, Vicodin, Xanax and Soma. One relative newcomer to the scene is Fentanyl, a painkiller that comes in the form of patches and lollipops and is 100 times more powerful than morphine.