The solution to America's addiction to painkillers may be … more drugs? A new study found a drop in painkiller overdose deaths in 13 states that allowed medical marijuana, CNN reports. That's because a patient prescribed marijuana will either stop taking opioids or take less of them, researchers theorize. From 1999 to 2010, researchers found that in the year following passage of a medical marijuana law, states saw a 20% decrease in opiate overdose deaths compared to states without one; that grew to 33% over the following six years, the Los Angeles Times reports. Abuse experts say marijuana may stem "runaway rates" of opioid overdose, which have tripled since 1991 in the US and are now responsible for 46 deaths per day, adds Newsweek.
The study's conclusion starts with two facts: It's "basically impossible" to die from a pot overdose, and the plant is less toxic than opiates, says the study's co-author. It can provide relief for many diseases—cancer, MS, HIV, glaucoma, chronic pain—and enhances painkilling drugs so less is needed. But the study isn’t without its critics. A drug policy expert tells CNN the study didn't consider whether methadone programs and law enforcement interventions helped decrease overdoses, and another says medical marijuana can't be a contributing factor because doctors don't widely prescribe it. Researchers say more study is needed—into pot's chemical composition, its effects on pain relief, and patient use. (Another study suggests that couples who toke together have less marital trouble.)