One-third of Americans who have taken prescription opioids for at least two months say they became addicted to, or physically dependent on, the powerful painkillers, according to a new Washington Post-Kaiser Family Foundation survey.

Virtually all long-term users surveyed said that they were introduced to the drugs by a doctor’s prescription, not by friends or through illicit means. But more than 6 in 10 said doctors offered no advice on how or when to stop taking the drugs. And 1 in 5 said doctors provided insufficient information about the risk of side effects, including addiction.

The survey raises sharp questions about the responsibility of doctors for an epidemic of addiction and overdose that has claimed nearly 180,000 lives since 2000. Opioid deaths surged to more than 30,000 last year, according to new data from the U.S. Centers for Disease Control and Prevention, with deaths from heroin alone surpassing the toll from gun homicides.

Doctors have been widely blamed for sparking the crisis by overprescribing highly addictive opioids to treat everyday pain. The survey suggests that they are still doing too little to stop it.

“Why isn’t it 100 percent?” demanded Gary Mendell, founder of Shatterproof, a grass-roots group dedicated to reducing addiction in the United States, referring to the share who say doctors have counseled them on stopping the medication. “It’s unbelievable that it’s not 100 percent.”

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