Editor’s note: If you or someone you know is struggling with suicidal thoughts or mental health matters, please call the 988 Suicide & Crisis Lifeline by dialing 988 to connect with a trained counselor, or visit the 988 Lifeline website.
Following the August 27 shooting at Annunciation Catholic School in Minneapolis, US Health and Human Services Secretary Robert F. Kennedy Jr. suggested that antidepressants may be a culprit behind mass shootings and other violence.
“We’re launching studies on the potential contribution of some of the SSRI drugs and some of the other psychiatric drugs that might be contributing to violence,” Kennedy told Fox News in an August 28 interview.
Selective serotonin reuptake inhibitors, commonly called SSRIs, are the most prescribed class of antidepressants for depression, anxiety disorders and many other mental health conditions. Several SSRIs have been on the market in the United States since the 1990s, including Prozac, Zoloft and Celexa.
Though journal entries by Robin Westman — the Minneapolis shooter who killed two children and injured 18 others before taking her own life — suggested she experienced mental or emotional distress, it has not been confirmed whether Westman had been taking antidepressants.
Expert consensus is that there is no scientific evidence of a causal nor correlational link between antidepressants and violence toward others. At least 11.4% of US-based adults took antidepressants in 2023, and that’s just for depression. Millions more adults and children take them for anxiety disorders, some eating disorders, post-traumatic stress disorder and more.
Mass shootings happen often in the US, but even with 340 million people and 393 million privately owned firearms in the US, they’re thankfully still rare events, said Dr. Keith Humphreys, the Esther Ting Memorial Professor in the department of psychiatry and behavioral sciences at Stanford University in California. “The odds that (mass shootings are) caused by SSRIs, when tens of millions of people are on them, seems pretty darn low to me. Even if 1% of people on SSRIs were going to do a mass shooting, we would have mass shootings every 10 minutes.”
Additionally, “the rate of homicide is generally pretty low, and then the rate of homicide for people who are treated with medications is only a subset of that,” said Dr. Rebecca Brendel, associate professor of psychiatry at Harvard Medical School and distinguished fellow of the American Psychiatric Association.
There is great risk in potentially vilifying one of the most prescribed medications that the US Food and Drug Administration has approved and determined to be safe and effective for the treatment of mental illness, Brendel said.
While some people don’t improve from antidepressants or experience negative side effects, many people experience improvement in their mental health symptoms that affect their happiness, daily functioning, work and academic performance, confidence, relationships and desire to live, she said.
“When we see acts of violence — especially acts of violence in places where our children, who we have a responsibility to protect, go to learn and to be safe — it breaks all of our hearts,” Brendel said. “That should drive us to want to do anything we can within our power and our ability to reduce the incidents of violence in this country.
“But conflating violence with mental illness or particular treatment for mental illness is not supported by the data and has a very, very grave risk of setting us backwards in terms of those with mental illness having access to the evidence-based care they need for the treatment of mental illness.”
A US Department of Health and Human Services spokesperson declined via email to answer CNN’s questions for this story.
The research on antidepressants and violence
Kennedy also told Fox News that “this kind of violence” is a “new thing in human history.”
“It’s not really happening in other countries,” he added. “We need to look at all of the potential culprits that might be contributing to that.”
This statement comes after about 100 employees, including researchers, were fired from the US Centers for Disease Control and Prevention’s violence prevention division in August due to downsizing by HHS — less than two weeks after a shooting attacking the CDC’s headquarters in Atlanta.
“He’s right about something: It’s not happening in other countries,” Humphreys said. But “other countries have plenty of people who take SSRIs. They’re one of the most widely prescribed drugs on Earth. So, if it were the SSRIs as opposed to something else that makes the United States different than every other country, we would see mass shootings like this all over.”
“What is unique about the United States is easy access to firearms,” Humphreys added.
Among mass shooters of the past several decades, about 4% of them had used antidepressants in their lifetime, and around 7% of them had used any psychotropic medication — rates far below baseline rates in the US, according to a study by Dr. Ragy Girgis that is currently under review for publication.
Girgis and the research team analyzed data from Columbia University’s Mass Murder database, “the largest database on mass shooters,” said Girgis, a professor of clinical psychiatry at Columbia University.
“Antidepressants most likely decrease violence, though this has not yet been directly tested,” such as in well-designed randomized clinical trials, Girgis said.
Patients often notice they can better handle frustration when on medication, said Dr. Jonathan Alpert, the Dorothy and Marty Silverman Chair of the Department of Psychiatry and Behavioral Sciences at Montefiore Medical Center in New York City.
Some people who suggest antidepressants may cause violence point to a 2020 Swedish study that found people on SSRIs had a higher rate of convictions for violent crimes, Humphreys said. But the authors themselves wrote in the study that their findings are correlations and may be influenced by participants’ personal issues or their reasons for taking antidepressants in the first place. Those who committed violence while on SSRIs were more likely to be male and have histories of violence.
Some mental health conditions can cause bouts of anger or aggression toward others and oneself when untreated, Humphreys said. Low levels of serotonin, a key feature of depression, are associated with violence, Girgis said. Drug use associated with these conditions can compound that likelihood.
Some people experience aggression when initially starting or quitting an antidepressant, but it’s usually in the form of verbal aggression and irritability that soon resolves itself, Girgis said.
Kennedy said many of the studies he claimed the National Institutes of Health is launching “have not been done in the past because of HIPAA regulations, which protect the privacy of patients.” He added that the federal government has the authority to bypass these regulations but also said it needs approval. Kennedy did not explain how the government would bypass that law or who would have to approve that action.
Kennedy also told Fox News that some antidepressants “have black box warnings that warn of suicidal ideation and homicidal ideation.” Suicidal ideation is “when you think about, consider or feel preoccupied with the idea of death and suicide,” according to the Cleveland Clinic. Homicidal ideation involves thinking about or considering harming or killing other people.
The black box, or boxed, warning refers to a prominent warning encased in a bold black border in the labeling or pamphlet of some medications. It’s meant to raise awareness of certain risks of taking the drug and to increase clinician monitoring of possible suicidality.
That some antidepressants have black box warnings for suicidal thoughts and behaviors among youth is true, experts said. Experts don’t fully understand why up to 4% of youth experience these symptoms when starting antidepressants, Alpert said.
But it may be partly due to a positive difference in how people feel about their suicidal thoughts, Girgis said. When people are sicker, suicidal thoughts are often ego-syntonic, meaning they’re more likely to want to act on them and not talk about them since people might interfere.
Once people start improving from medication, those thoughts become disagreeable to them, so they report them to seek help. This trend could be why the risk typically doesn’t lead to more actual deaths from suicide, Girgis added.
That some antidepressants in the US have warnings of homicidal ideation, however, is not true, according to experts interviewed for this story. It seems only one antidepressant, Effexor, previously included homicidal ideation on its list of rare adverse events.
In the FDA’s reporting system for adverse events, for the six common antidepressants — starting with Prozac in 1988, through 2024 — there have been 698 adverse events of homicide reported and 808 reported adverse events of homicidal ideation, said Dr. Linda Martin, a member of the Southern Network on Adverse Events, a national drug safety group based at the University of South Carolina.
Adverse events can be reported by drug manufacturers, health professionals or consumers, and “may contain incomplete, inaccurate, untimely, and/or unverified information,” according to the FDA. There isn’t any information on the nature of, or context around, the reports for the six antidepressants nor any comparison that would indicate whether these numbers are higher than those in the general population or among people on other medications, Humphreys said. Millions of people take antidepressants, and events being reported doesn’t always mean they’re linked to the drug.
Antidepressant packaging inserts have four sections that can address possible adverse events: boxed warnings, warnings and precautions, post-marketing experience and the medication guide. But of the labels for the six antidepressants Martin analyzed, she found that only the medication guide sections mention the word “violent.” The medication guide for Prozac, for example, instructs patients to call their health care provider or 911 if they are “acting aggressive or violent” or experiencing multiple other symptoms. Eli Lilly, the manufacturer of Prozac, declined to comment.
Drug packaging inserts often mention any event that was observed or measured in studies in which antidepressants were given, and some of those have observed a 1% incidence of homicidal ideation, Girgis said.
Martin contends that the adverse events should be mentioned in the post-marketing warning sections of packaging inserts, she said.
“I am entirely in favor of rigorous, unbiased research on the risks and benefits of all medications, including antidepressants,” Alpert said. “I don’t have any knowledge of any intentions to selectively withhold data from the public, but I certainly welcome transparency on this topic across all drug companies and all medications. Both as prescribers, patients, and people who have loved ones on medications, we all want clear, accurate and consistent information and should continue to work toward this goal.”
Anyone with questions about antidepressants should speak with their prescribing physician, Brendel said.
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