Landmark Review Finds No Evidence for Medical Marijuana in Treating Common Mental Health Conditions
A groundbreaking new analysis, the largest of its kind to date, has concluded there is "no evidence" that medical marijuana is effective in treating anxiety, depression, or post-traumatic stress disorder (PTSD). This comprehensive review, which examined 54 international trials published over a span of 45 years, could significantly alter the medical landscape regarding cannabis use.
Contradictory Findings and Rising Usage Trends
While some experts have previously suggested marijuana might reduce stress and anxiety, research from the Centers for Disease Control and Prevention (CDC) indicates the drug can actually heighten symptoms of these mental health disorders. The Australian authors behind the new study argue these findings highlight an urgent need for greater regulation of medical marijuana.
"Though our paper didn’t specifically look at this, the routine use of medicinal cannabis could be doing more harm than good by worsening mental health outcomes," explained lead author Dr. Jack Wilson from The University of Sydney. "This includes a greater risk of psychotic symptoms, developing cannabis use disorder, and delaying the use of more effective treatments."
Alarming Statistics on Substance Use in America
The study emerges against a backdrop of soaring marijuana use in the United States. Federal data from 2024 reveals more than 48 million Americans are battling a substance use disorder. Furthermore, the National Survey on Drug Use and Health reports over 22 million Americans aged 12 and older struggled with a marijuana use disorder in the past year, a significant increase from 19 million in 2023.
Marijuana remains the most commonly used federally illegal drug in the U.S., with the CDC reporting 52.5 million Americans used it at least once in 2021. A Gallup survey showed the number of people who smoke marijuana more than doubled from 2013 to 2024, reaching historic highs.
The Medical Marijuana Landscape and Associated Risks
Medical marijuana is currently legal in 40 states and Washington, D.C. Researchers estimated in 2021 that approximately three million Americans use it medically, a number that is steadily growing. Many of these users are older adults disproportionately affected by chronic disease and long-term pain.
However, researchers warn of significant physical and mental risks associated with regular marijuana use, particularly for individuals over 65. Studies from Stanford Medicine found regular use correlated with a 29 percent increase in heart attacks and a 20 percent increase in strokes.
"There is no safe amount of cannabis. Low doses and occasional use are still associated with vascular inflammation," stated Dr. Joseph Wu, director of the Stanford Cardiovascular Institute. "Abstinence is the safest option for heart health."
Nuanced Findings and Broader Implications
The new analysis did acknowledge that medical marijuana "may be beneficial" for certain other conditions, such as pain and multiple sclerosis, with two October studies showing it could help alleviate back pain. However, the researchers cautioned that the overall quality of evidence for conditions like autism and insomnia was low, and those results should be treated "with caution."
The review also noted that medicinal marijuana was found to increase cravings for cocaine among people living with cocaine-use disorder. For individuals with marijuana dependency, the analysis suggested an oral form could be helpful "when administered alongside psychological therapy."
A separate study published by Johns Hopkins Medicine on the same day found that young people with marijuana use disorder were more likely than others with different substance use disorders to be diagnosed with a psychiatric disorder, a correlation not observed in adults.
This landmark review underscores the complex and often misunderstood relationship between cannabis and mental health, calling for more rigorous research and cautious clinical application.
