Experts clash over anti-depressant link to homicides

THE COLLEGE of Psychiatry of Ireland has said there is no evidence of a link between anti-depressants and homicide.

THE COLLEGE of Psychiatry of Ireland has said there is no evidence of a link between anti-depressants and homicide.

It said the mooted link between anti-depressants and violence did not have a basis in scientific evidence and it risked perpetuating a “false and stigmatising stereotype” that people with mental illness were violent. The college issued the statement in response to evidence given at an inquest in Wicklow last month into the death of Shane Clancy (22).

A medical witness who provided evidence that there was a link between these drugs and violence and suicidal acts yesterday rejected the college’s position.

Prof David Healy of Cardiff University school of medicine in Wales described it as “astonishing” the college would say there was no scientific basis to claims there were risks.


The inquest returned an open verdict after hearing Clancy had toxic levels of anti-depressants in his body when he killed himself, after fatally stabbing Sebastian Creane and injuring two other people in Bray last August.

Clancy’s mother, Leonie Fennell, said her son had become increasingly agitated after taking the anti-depressant and his behaviour while on the drug was “not the Shane we knew”.

Prof Healy told the inquest Clancy’s actions were “extraordinarily rare” but it did happen that such drugs contributed to a patient’s problem and made it worse in a small number of cases.

Coroner for east Wicklow Dr Cathal Louth, refused a request by the College of Psychiatry in Ireland to allow it to question Prof Healy’s evidence.

Afterwards, psychiatrist Prof Patricia Casey, who attended the inquest, expressed disappointment on behalf of the college.

The college later said it would respond after the inquest of Mr Creane had been held.

In the statement, the college said there had been considerable discussion of suicidality and homicidality as potential adverse effects of antidepressant medications, particularly elective serotonin re-uptake inhibitor (SSRI) anti-depressants.

“Much of this discussion has been speculative. Clearly, suicide and homicide are events of the utmost gravity and any possible role of any treatment in precipitating such tragedies warrants the most thorough investigation,” it said. “However, discussion of the risks involved must be based on evidence rather than conjecture or unfounded personal opinion.”

The statement said there could be a period, early in treatment, when the illness was unresponsive, before the benefit of the antidepressant could be seen.

“This leads to a period of risk following commencement which requires additional non-pharmacological support.

“Anecdotal cases of suicide sometimes mistakenly attribute these tragic events to the treatment rather than the illness itself.”

It also said people who were beginning to respond to anti-depressant treatment may have more energy and motivation to act on suicidal thoughts.

“That the early recovery period is potentially a period of increased risk for suicidality is something of which all doctors should be aware,” it said. The college recommended close monitoring of all individuals starting on anti-depressant therapy.

“There is no evidence of a link between anti-depressant use and homicide. Commentators who assert that there is such a link rely largely on a small number of case reports of individuals who were homicidal after commencing anti-depressants. However, case reports cannot demonstrate a causal link.

“Homicide by people who have recently started anti-depressants is incredibly rare, but it occurs. Anti-depressants do not cause violence. Neither are they, nor can they be expected to be, an inoculation against violence.”

Responding yesterday, Prof Healy said there was clinical trial data that supported a link between anti-depressants and violence and both British and US regulatory bodies had drawn a link between the use of these drugs and suicidal acts.

“There is a general acceptance that anti-depressants can in some people induce a state of agitation, and also an emotional dissociation, and finally can precipitate psychosis.

“They may disagree with the data but to state there is no evidence or that the suggestion there are risks is based on conjecture is plain wrong,” Prof Healy said.