AN involuntary patient in Bunbury Regional Hospital's psychiatric unit most likely died from a seizure brought on by a combination of her antidepressant medication, too much water and vomiting, a coroner has found.
Gillian Hanson, 62, died in her room in the unit's closed ward in June 2010 after displaying psychosis symptoms the night before.
Psychosis is a severe mental episode that usually results in sudden derangement and loss of contact with reality.
But on Tuesday the coroner cleared staff of any wrongdoing.
Ms Hanson had been "excessively unwell" and after a visit from a psychiatrist at her home she was admitted to the hospital involuntarily.
On the day she died a nurse went to give Ms Hanson Maxolon, a drug used to treat nausea and vomiting, but found she was asleep.
When staff checked on her again she was found sitting on her bed and talking to herself, but appeared calm.
When they returned a third time they found she had collapsed and was unresponsive.
Despite efforts to "aggressively" resuscitate Ms Hanson, she was pronounced dead.
Blood taken before resuscitation fluids were administered revealed a very low level of sodium at her time of death.
The coroner said Ms Hanson's medication likely contributed to the low sodium level and recommended the need for more awareness among clinicians about the potential problem.
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