© UnknownMarie McCracken was subjected to a prolonged and brutal attack by Torlay
Marlene Torlay, 61, attacked Mary McCracken, 59, with scalding water, a hammer and a knife sharpener, at her home in East Kilbride, in October 2012.
The Crown accepted her guilty plea to a reduced charge of culpable homicide due to diminished responsibility.
Torlay was ordered to be detained under an interim compulsion order at Royal Edinburgh Hospital's Orchard Clinic.
The High Court in Edinburgh heard that she had been prescribed too high a dose of an anti-depressant which could cause acute withdrawal symptoms, and may have missed a dose of the drug.
The court heard that Torlay was friends with Mrs McCracken, who was known as Marie and was a senior service assistant for the WRVS at Hairmyres Hospital in East Kilbride.
'Brutal attack'
On 24 October 2012, Mrs McCracken called at her friend's house, in South Lanarkshire, for a cup of tea and a chat.
During the visit she was subjected to "a prolonged and brutal attack", in which Torlay threw scalding water at her before repeatedly striking her on the head and body with a hammer and knife sharpener.
The court heard that following the fatal attack, Torlay looked in a mirror and saw her face and clothes were covered in blood.
She then started to clean up after putting a throw over the victim's body.
Later that day, her son returned to the house and found his mother sitting watching television unaware that Mrs McCracken's body was lying in another room.
She later said her friend had told her to take a tablet and calm down, but Torlay found herself "hitting and hitting and hitting her".
It emerged in court that the 61-year-old widow had developed depression about 18 months before the attack and was prescribed an anti-depressant drug, citalopram.
Defence counsel Ian Duguid QC said a psychiatrist who had prepared a report in the case said she was prescribed "a dosage which was far in excess of what she should have been prescribed".
'Wrong dosage'
Acute withdrawal symptoms to the drug - which can include confusion, irritability and aggression - may occur after missing a single regular dose.
The counsel said: "It is not for me to comment that the wrong dosage of an anti-depressant drug explains, or goes to explain, the violent conduct of Mrs Torlay.
"But clearly there is some issue that might properly have been investigated at an earlier stage as to whether or not she was being properly treated for a depressive illness."
Mr Duguid told the court that since Torlay's admission to hospital she had been slowly weaned from the drug and given a different anti-depressant.
Advocate depute Jonathan Brodie QC said there was some evidence to indicate that Torlay may have missed a dose of her medication on the day of the offence or shortly before.
Judge Lord Jones ordered that Torlay should be detained under an interim compulsion order at the Orchard Clinic.
He said he was satisfied on psychiatric evidence that Torlay has a mental disorder.
Sadly, far too few patients suffering from depression who are prescribed dangerous antidepressant drugs by callous irresponsible money grubbing doctors and shrinks end up killing those same medical malpracticioners.
More's the pity, but failing that we need laws to strip those doctors of their medical licenses, put them in prison for criminally negligent homicide, and prosecute the big pharmaceutical companies completely out of business for pushing those drugs. After about five years the problem will be solved.