As an analogy, Volkow said opiate addicts are more sensitive to pain, as their overuse of drugs have raised the threshold at which the body responds and their own bodies produce fewer natural opiates.
NIDA is seeking proposals from researchers who want to investigate such possibilities for cannabis, she said.
Proponents of legalizing marijuana disagree with the official line. Krissy Oechslin of the Marijuana Policy Project disputes the finding that cannabis products are stronger.
"They make it sound like the THC levels in marijuana were almost nonexistent, but no one would have smoked it then if that was true," she said.
"And there's evidence that the stronger the THC, the less of it a person smokes. I don't want to say it's good for you, but I'll say [more potent marijuana] is less bad for you."
While Walters stresses that drug abusers are patients and not criminals, he hopes to crack down more on producers. And he says, there is a way to go in getting cooperation from local law enforcement officials. "For many in enforcement, marijuana is still `kiddie dope,'" Walters said.
He is quick to stress he does not want to overreact.
"We shouldn't be victims of reefer madness," he said, referring to the 1930s propaganda film Reefer Madness that became a 1970s cult classic for its over-the-top scenes of marijuana turning teenagers into homicidal maniacs.
RSS