Warnings that some prescription drugs cause violent thoughts

When it comes to cocaine, crystal meth or LSD, there is no difficulty believing a drug could drive a person to commit a crime.

However, in the case of prescription drugs, the drug is always innocent and the person guilty, a psychiatrist has said.

David Healy, an Irish-born professor based in the UK, has been an expert witness in homicide and suicide trials involving psychotropic drugs. He believes selectove serotonin re-uptake inhibitor (SSRIs) anti-depressants can cause a delirium that leads to violent behaviour.