Fewer Painkiller Deaths in States With Medical Pot
People with chronic pain may use pot instead of narcotics, researchers suggest
Since 2010, another 10 states and Washington, D.C., have adopted similar laws, the researchers said.
While overdose deaths have risen in all states, Bachhuber and his colleagues found that the annual average number of deaths caused by painkillers is nearly 25 percent less in states with medical marijuana laws.
"In absolute terms, states with a medical marijuana law had about 1,700 fewer opioid painkiller overdose deaths in 2010 than would be expected based on trends before the laws were passed," Bachhuber said.
States' overdose death rates decline an average 20 percent in the first year following the passage of a medical marijuana law, the researchers found. By the second year, overdose death rates on average decline 25 percent, and as much as 33 percent by five years after legalization of medical pot.
Medical marijuana laws also are associated with a more dramatic decrease in overdose death rates than other means commonly used to tackle prescription drug abuse, the study noted.
For example, prescription drug monitoring programs are associated with an average 3.7 percent increase in overdose deaths, compared with a 24.8 percent decline associated with medical pot legalization, according to the study.
Increased state oversight of pain management clinics is associated with a 7.6 percent decline in overdose deaths, while laws requiring patients to show ID when picking up a prescription are associated with a 5 percent increase in overdose deaths, the study authors found.
Bachhuber cautioned that the exact mechanism underlying these study results is unclear, and that the findings don't prove a direct cause-and-effect relationship between medical marijuana laws and overdose deaths.
Flansbaum agreed. Although he called the paper "provocative" and "stimulating," he said it doesn't prove that medical marijuana reduces drug overdoses.
"There are so many things going on in states, whether it be cultural or through laws, it's hard to say what's the effect of the medical marijuana law versus everything else that's happening," Flansbaum said. "You don't know what causes what. The data is not that clean."
But these findings support previous studies that showed people who receive a prescription for medical marijuana tend to reduce the amount of other pain medications they use, said John Thomas, a health law expert and professor at the Quinnipiac University School of Law in Hamden, Conn.