Recreational Cannabis Legalization Reduces Demand for Prescription Drugs, Study Finds
The legalization of adult-use recreational cannabis has also lessened demand for prescription medications such as sleep aids, pain medications, and antidepressants, according to a new study from researchers at Cornell University and Indiana University.
The research, published this month in the journal Health Economics, looked at quarterly prescription drug data reported by all 50 state Medicaid programs from 2011 to 2019. It found that when states legalized cannabis, the volume of prescriptions given out for drugs related to managing pain, depression, anxiety, sleep, psychosis, and seizures all decreased significantly.
While the researchers do caution that excessive cannabis use is not without its own harms, they say that this substitution of prescription drugs for cannabis could be important in terms of harm reduction strategy and in potential cost savings for state Medicare programs.
Demand for some prescription medications falls following legalization
Using Medicaid State Drug Utilization Data (SDUD) provided by the Centers for Medicare and Medicaid Services, the researchers examined quarterly prescription data for nine different classes of drug between the years 2011-2019. During this time, eleven states implemented recreational cannabis policies: Alaska, California, Colorado, Maine, Massachusetts, Michigan, Nevada, Oregon, Vermont, and Washington.
The researchers found significant reductions in Medicaid prescribing rates following the implementation of recreational cannabis laws in six of the nine drug classes studied. These were drugs used for pain, depression, anxiety, sleep, psychosis, and seizures. Drugs used to treat nausea, spasticity, or glaucoma were unaffected by local cannabis policy.
The largest reductions in prescribing rate were seen in drugs utilized for anxiety, depression, sleep, and psychosis, which all fell by between 10 to 12 percent after recreational cannabis legalization.
“These results have important implications,” said first author Shyam Raman, a doctoral student at Cornell University, in a statement. “The reductions in drug utilization that we find could lead to significant cost savings for state Medicaid programs. The results also indicate an opportunity to reduce the harm that can come with the dangerous side effects associated with some prescription drugs.”
Substitution is already known to happen in medical-use states
One of the most commonly cited early concerns with the establishment of medical cannabis programs and legalization of recreational cannabis was that cannabis would act as a gateway drug, encouraging broader increases in drug use.
Despite this fear, early studies of medical cannabis legalization have suggested that almost the opposite is true; that the implementation of medical cannabis programs has reduced the use of prescription drugs for which cannabis could serve as a clinical alternative.
Another study estimated that this substitution of cannabis for costly prescription drugs could have saved more than $1 billion for fee-for-service Medicaid if all states had adopted a medical cannabis program in 2014.
Some reports indicate that cannabis legalization may also reduce the use of prescription opioids, though other studies have not found similar substitutions with illicit opioid use.
Medical and recreational legalization could have different impacts on drug use
Similar studies to this new prescription demand study have been conducted in the past, focusing on the effects of medical cannabis legalization.
Interestingly, this new recreational cannabis study reports finding reductions in drugs used to treat sleeping problems and anxiety disorders, which were not observed in medical-only studies. The researchers say that this may suggest that the conditions for which prescription drugs are being substituted could differ depending on the type of cannabis legislation in place.
The researchers do note several limitations on this new study. Primarily, since the data are reported at the state level, there is no way to measure the effect of recreational cannabis legalization at the individual-level or investigate whether different demographic groups are affected in different ways. This also means that it is impossible to confirm whether individual patients are indeed substituting their pharmaceutical prescription drugs for cannabis, although the aggregate data would suggest this.
While cannabis can offer potential harm reduction benefits compared to medications with intense side effects or a risk of abuse and dependence, the researchers are also careful to caution that excessive cannabis use carries its own risk. For example, frequent cannabis use is associated with an increased risk of developing schizophrenia.
“We must also consider the possibility that an increase in patients using cannabis to treat their medical conditions may have the unintended consequence of creating more distance between individuals and their medical providers,” the study authors wrote.
As newer data become available, the researchers say they hope that further studies will be able to “fully decompose the costs and benefits associated” with state-level cannabis legalization.
