A patient died after being given an overdose of six bottles of medication – when he was prescribed less than a teaspoon, a report has found.
Joshua Gaffney, 22, who should have received less than a third of a bottle, had 21 times the prescribed amount of the drug clozapine.
He died at home in Yeovil, Somerset, shortly after the liquid was administered allegedly in the presence of mental health nurses Amanda Young and Petia Gummer.
A post-mortem examination and toxicology report found Joshua died from “acute clozapine toxicology” after being given 84ml instead of just 4ml.
The nurses were arrested and charged with Joshua’s manslaughter but police have formally dropped the allegation.
Joshua’s devastated mother, Tina Marren, also of Yeovil, said she was “shattered” by the decision.
She said: “My son was my life and that was taken away. I will never give up until I get answers for Joshua.
“He was a wonderful, lovely person.
“I feel the authorities are treating Joshua as if he was not important. As a family we are so angered, hurt, and devastated.”
Joshua, who was being treated for mental illness psychosis, died at his home in Yeovil after being visited by Miss Young and Mrs Gummer on February 8 last year.
A post mortem examination and toxicology report later found the cause of his death was “acute clozapine toxicity”.
It states that Joshua was given six full bottles of the drug – equal to 4,200mg or 84ml when his prescribed dosage was 200mg or 4ml.
The nurses, who work out of Summerland Hospital in Yeovil, have been suspended by their employer Somerset Partnership NHS Foundation Trust.
They are subject to separate investigations by the trust and regulator the Nursing and Midwifery Council, who have placed restrictions on them.
A report of a condition of practice hearing for Mrs Gummer said: “The panel noted that Mrs Gummer denies the allegations.
“However, having considered the serious nature of the allegations, which involved a gross inaccuracy in drug administration, the panel considered that there is a real risk of repetition of the alleged behaviour should Mrs Gummer continue to practise without restriction.”
A spokeswoman for the Nursing and Midwifery Council said investigations would continue and a panel would decided whether the nurses had a case to answer.
She added: “If this is the case there will be a substantive hearing by the conduct and competence committee.”
The Somerset Partnership NHS Foundation Trust said it would conduct its own internal investigation following the decision not to bring criminal charges.
A spokesman added: “The trust would like to express its sincere condolences to Joshua’s family. The nurses involved in the incident remain suspended from work.
“The findings of this investigation will be shared with Joshua’s family, the national inspectorate – the Care Quality Commission and the local Primary Care Trust.”
An inquest into Joshua’s death has been opened and adjourned by East Somerset Coroner Tony Williams.
His family are now preparing their case for the coroner along with a solicitor and say they will fight for answers to Joshua’s death.
Joshua’s aunt Lorraine Marren, 44, said: “We as a family are not allowed to say everything we would like to say about what happened to Joshua as this could still jeopardise the ongoing investigations.
“We will not give up fighting until the whole story is out – not only for Joshua but for every other family out there who need to be aware of this terrible tragedy.”
A spokeswoman for the Crown Prosecution Service confirmed that the charges against the two nurses had been dropped.
She said: “The CPS received material from the police in relation to the matter and provided them with early advice on their investigation.
“We did not, however, receive a full file of evidence in this case.
“The decision to take no further action was made by the police. Our thoughts remain with Joshua’s family.”
A spokesman for Avon and Somerset police added: “We received extensive advice from the Crown Prosecution Service on this matter and we were guided to the fact that we would not succeed in a prosecution in this case.”
Joshua’s inquest is due to be reconvened later this year.
Both nurses declined to comment through the Somerset Partnership NHS Foundation Trust.