The family of a woman who died in March 2004 have heard about how a possible mistake made by a doctor may have been responsible.
At the age of 72, Doreen Froste passed away at Huddersfield Royal Infirmary, the Huddersfield Examiner reports.
She had been prescribed a drug for arthritis by her GP Dr Manohar Singh.
He told her to take Methotrexate in five-per-week daily doses between October 2003 and February the following year.
The medical expert is accused of a number of failures, including not carrying out blood and liver tests to monitor the effects of the treatment.
During a tribunal, expert witness Dr Ian Isaac told the panel Dr Singh had made a "serious prescribing error" and his care of Ms Froste had been "substandard".
An inquest held in 2008 ruled that the pensioner's death had partially been caused by poisoning
A tribunal at the General Medical Council - which exists to registers doctors to practise medicine in the UK - is ongoing in Manchester.