Last updated on: 6/14/2012 | Author:

Daniel K. Hall-Flavin, MD Biography

Consultant in the Department of Pysciatry and Psychology at the Mayo Clinic
Not Clearly Pro or Con to the question "Should Marijuana Be a Medical Option?"

“Some research suggests that marijuana smokers are diagnosed with depression more often than are nonsmokers — particularly regular or heavy marijuana users. However, it doesn’t appear that marijuana directly causes depression. It’s likely that the genetic, environmental or other factors that trigger depression also lead to using marijuana. For example, some people may use marijuana as a way to cope with depression symptoms.

There are also links between marijuana and other mental health conditions. Marijuana use may trigger schizophrenia or detachment from reality (psychosis) in certain people. There is also some evidence that adolescents who attempt suicide may be more likely to use marijuana than those who don’t. As with marijuana use and depression, more research is needed to better understand these associations.

The bottom line: Marijuana use and depression accompany each other more often than you might expect by chance, but there’s no clear evidence that marijuana directly causes depression.”

“Expert Answers: I’m curious about marijuana and depression. Can marijuana cause depression?,” Mayo Clinic website (accessed June 11, 2012):

Involvement and Affiliations:
  • Associate Editor, Philosophy, Ethics and Humanities in Medicine, 2009-present
  • Co-Chair, Treatment Improvement Committee, American Academy of Addiction Psychiatry, 1999-present
  • Consultant, Department of Pysciatry and Psychology, Mayo Clinic, 1999-present
  • Assistant Professor of Psychiatry, Mayo Clinic College of Medicine, 1996-present
  • Medical Director, National Council on Alcoholism and Drug Dependence, 1986-1999
  • Faculty member, Cornell University Medical College
  • Faculty member, New York Medical College
  • Faculty member, George Washington University Medical School, 1993-1994
  • Recipient, Alumni Achievement Award, University of Missouri at Kansas City, 1987
  • Fellowship, Chemical Dependency Fellowship, Mayo Foundation Scholar, Cornell University, 1983-1984
  • Residency, Adult Psychiatry, Mayo Graduate School of Medicine, College of Medicine, Mayo Clinic, 1980-1983
  • Internship Fellow, Internal Medicine, Mayo Graduate School of Medicine, College of Medicine, Mayo Clinic, 1979-1980
  • MD, University of Missouri at Kansas City, 1979
  • BA, Biology, University of Missouri at Kansas City, 1978
  • Special interests in adult psychiatry, addiction psychiatry, pharmacogenetics and personalized medicine
Quoted in:
  1. Is Medical Marijuana an Effective Treatment for Depression, Bipolar Disorders, Anxiety, and Similar Mood Disorders?