NEW YORK – From the moment news emerged Friday that a young man had carried out a horrific massacre of elementary-school children, politicians from local city halls to the White House have been restoking the age-old push for more gun control. While guns have been a common denominator in mass slayings at schools by teens, there's another familiar element that seems increasingly to be minimized.

Some 90 percent of school shootings over more than a decade have been linked to a widely prescribed type of antidepressant called selective serotonin reuptake inhibitors or SSRIs, according to British psychiatrist Dr. David Healy, a founder of RxISK.org, an independent website for researching and reporting on prescription drugs.

Though there has been no definitive confirmation that drugs played a role in the Newtown, Conn., assault, that killed 20 children and six adults, media have cited family members and acquaintances saying suspect Adam Lanza was taking prescription medication to treat "a neurological-development disorder," possibly Aspergers.

Healy cautioned that the public needs "to wait to find out what Adam Lanza was on, and whether his behavior does fit the template of a treatment-induced problem."

However, in an email to WND, he said he suspected prescribed psychiatric medications was the cause of Lanza's violent behavior.

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Healy said that while the public waits to learn more about Lanza, there are two general points that can be made.

First, he said, "psychotropic drugs of pretty well any group can trigger violence up to and including homicide."

"Second, the advocates of treatment claim both that it is the illness and not the drugs that causes violence and that we are leaving huge numbers of people untreated."

But Healy argued that if this were the case, "we should not find that comfortably over 90 percent of school shootings are linked to medication intake."

Dr. Peter R. Breggin, a Harvard-trained psychiatrist and former full-time consultant at the National Institute of Mental Health, told WND it's likely that problems for Lanza began with "getting tangled up" with psychiatric medicine.

Breggin insisted there has been overwhelming scientific evidence for decades correlating psychiatrically prescribed drugs with violence.

Writing in Ethical Human Sciences and Services, a peer-reviewed scholarly journal, in 2003, Breggin concluded SSRI drugs could be a factor in suicide, violence and other forms of extreme abnormal behavior, as evidenced in case reports, controlled clinical trials, and epidemiological studies in children and adults.

Since the 1970s, Breggin has testified in approximately 100 trials, including one in which Judge Robert Heinrichs ruled the adverse effects of taking Prozac drove a 16-year-old in Winnipeg, Canada, to commit an unprovoked murder.

Breggin appeared before the Veterans Affairs Committee of the U.S. House of Representatives in 2010 in support of his 2008 book "Medication Madness: The Role of Psychiatric Drugs in Cases of Violence, Suicide and Crime."

Breggin testified to Congress that research conducted in the medical science demonstrates a causal relationship between antidepressant drugs and the production of suicide, violence, mania and other behavioral abnormalities.

He warned Congress of the risks of giving these drugs to heavily armed young men and women in the military.

Mainstream religion

Breggin asserted that establishment media "ignores the scientific evidence linking psychiatric medications and violent behavior because psychiatry is the religion of the mainstream media, and they don't want to see the dangers of psychiatrically prescribed drugs."

"Besides, the drug companies also have incredible influence through advertising such that they can call the shots," he said.

He believes the Lanza case fits the pattern of school shooters in some of the most famous incidents in recent memory, including the 1999 shootings at Columbine High School in Colorado and the massacre at Virginia Tech in 2007.

"Adam Lanza has in common with many of the young men who were shooters that they were outsiders who lived in the shadows, who deal with a lot of shame, humiliation and isolation," Breggin explained.

He calls the psychiatric diagnoses "worthless."

"We know exactly who they are," he said. "They are called ‘geeky' in the extreme. Not a single one has ever come forward with a close friend. They are alienated from their families, and they have been involved in psychiatry."

Breggin insists that instead of psychiatric treatment, children of this kind need "more reaching out, more socialization, more caring, more involvement."

"Our schools, our families, and our communities need to be aware of the kids who are withdrawn and violent, not because they are going to become violent – hardly any of them are going to become violent – but because these are really hurt kids," he said.

"We can call them evil, we can call them mentally ill, but the pattern is really quite clear," Breggin continued. "They are highly intelligent and highly withdrawn and they are all involved with psychiatry, so the claim psychiatry is going to do some good is really ridiculous."

In many school shootings carried out by minors, court documents are sealed and the extent of chemical use is unknown to the public.

But in a number of high-profile cases, the link has been reported:

Kip Kinkel was withdrawing from Prozac and had been prescribed Ritalin when he murdered his mother and stepfather then shot 22 classmates, killing two, in 1998.

Christopher Pittman was withdrawing from Luvox and from Paxil when he killed his paternal grandparents in 2001.

Elizabeth Bush, who fired at fellow students in Williamsport, Pa., in 2001, wounding one, was on Prozac.

Jason Hoffman, was on Effexor and Celexa when he opened fire at his El Cajon, Calif., high school, wounding five.

Shawn Cooper of Notus, Idaho, was on antidepressants when he fired a shotgun on students and staff.

T.J. Solomon, on antidepressants, wounded six at his Conyers, Ga., high school.

Eric Harris was taking Luvox when he and fellow student Dylan Klebold killed 12 students and a teacher and wounded 24 others before turning their guns on themselves at Columbine High School in Colorado.

At Virginia Tech in 2007, where 32 were murdered, authorities found "prescription medications related to the treatment of psychological problems had been found among Mr. Cho's effects," according to the New York Times.

"Violence and other potentially criminal behavior caused by prescription drugs are medicine's best kept secret," Healy said in a statement last month. "Never before in the fields of medicine and law have there been so many events with so much concealed data and so little focused expertise."

In the past six years, Healy has authored two best-selling books analyzing the degree to which the pharmaceutical industry has influenced medical doctors to prescribe antidepressant drugs to patients with psychiatric problems: "Let Them Eat Prozac: The Unhealthy Relationship Between the Pharmaceutical Industry and Depression," in 2006 and "Pharmageddon" in 2012.

Recently, Healy's RxISK.org added a "violence section" to its website, allowing users to enter the name of a prescription drug to find out the side effects recorded in the more than 4 million adverse drug event reports filed with the FDA since 2004.

Was Lanza on meds?

Writing for Slate.com Monday, Emily Willingham was quick to warn against demonizing Asperger's syndrome, or autism in general, as the cause of Lanza's violence. Likewise, in a New York magazine piece titled "Asperger's is a Red Herring to Explain the Newtown Massacre," Adam Martin wrote, "As the nation sets out to understand how Friday's massacre came to pass, some are rightly worried that the high-functioning form of autism will become unfairly stigmatized."

Nevertheless, credible sources have not withdrawn published claims that Lanza was on prescribed psychiatric medication at the time of the shooting.

On CBS's "60 Minutes" Sunday, Mark and Louise Tambascio, friends of the shooter's mother, Nancy Lanza, said Adam Lanza was being medicated for Asperger's.

"I know [Adam Lanza] was on medication and everything, but she homeschooled him at home cause he couldn't deal with the school classes sometimes," Louise Tambascio told CBS reporter Scott Pelley. "So she just homeschooled Adam at that home. And that was her life."

Her comment followed Mark Tambascio explaining to Scott Pelley that "friends told us that [Asperger's syndrome] did dominate the Lanzas' lives."

In addition, the Washington Post reported over the weekend an unnamed former neighbor of Nancy and Adam Lanza in Newtown, Conn., recalled Adam as "a really rambunctious kid" who "was on medication."

The story became confused when a now discredited source claiming to be Adam Lanza's "Uncle Jonathan" told several publications, including the Sun in the United Kingdom, that Adam was being treated with the strong anti-psychotic drug Fanapt.

Later reports found no relatives who knew "Uncle Jonathan."

Separately, law enforcement officers have found evidence Lanza played graphically violent video games, the Hartford Courant reported on Sunday.

The Express in the United Kingdom reported Monday that Lanza had "an unhealthy obsession for violent video games" and that his favorite video game was said to be a "shockingly violent" fantasy war game called Dynasty Warriors, which is "thought to have given him inspiration to act on his darkest thoughts."