A coroner ruled that a hospital’s safeguards were “inadequate” when a pensioner was killed with a massive overdose of heart medication.

Joan Dixon was given ten times too much digoxin at St Richard’s Hospital in Chichester after a junior doctor prescribed milligrams instead of micrograms.

Hospital officials say they have made changes to prevent the mistake happening again.

Mrs Dixon, of High Street, Findon, near Worthing, broke her hip in September 2010.

Dr Prashen Pillay, who had failed to progress in his training from an earlier stint at the Royal Sussex County Hospital in Brighton, prescribed her 250 milligrams of digoxin instead of 250 micrograms by mistake, writing the abbreviation “mg”.

The inquest heard NHS practice is to write the word in full, but he said there was not enough room on the prescription form.

In the event the pharmacy gave out 2.5 milligrams, its standard amount, without checking the amount requested. This was ten times the intended dose. Mrs Dixon’s cause of death was given as “digoxin toxicity”.

Her daughter, Carolyn, read a statement at the hearing at Park House, Horsham, criticising her mother’s care in general in the lead-up to her death, saying she “deserved better of the NHS”.

She said: “The repeated failure of any one of all the people involved in her health care to take responsibility and put my mother’s interests first . . . made the making of mistakes more likely.”

She accepted an apology from Dr Pillay at the inquest.

West Sussex Coroner Penelope Schofield recorded a narrative verdict, saying: “The safeguards in place at the time were inadequate to prevent this unfortunate chain of events from occurring.”

After the inquest, Dr Phillip Barnes, medical director of Western Sussex Hospitals NHS Trust, which runs St Richard’s, said: “We are all sorry that a terrible, one-off accident such as this could have happened at our trust.

“Safeguards have been strengthened in the last two years. We have strengthened all of our medicines management processes including additional training for nursing and junior doctor staff and changes to how we handle stock drugs on different wards.

“In addition, junior doctors are now assessed for prescribing competency.”