Mental illness is putting huge pressure on WA's hospitals, with 21,507 mental health patients admitted to major city emergency wards in the past year at a cost of more than $10 million.
Hospital figures show mentally ill people make up as much as a fifth of emergency ward admissions with a 20 per cent jump in December compared with that month in 2009.
Doctors say emergency wards are the wrong places to treat mentally ill patients who need specialist care and where high levels of noise and stress can worsen their condition.
But a shortage of psychiatric beds means mentally ill patients stay in emergency departments up to six days.
Australian Medical Association WA president David Mountain said the proportion of mentally ill people in emergency wards had risen dramatically.
"Clearly these patients are high maintenance," he said. "It's a terrible environment for these patients. It's extremely stressful.
"These patients are more likely to have violent outbursts and need to be restrained."
Associate Professor Mountain said some patients went to emergency departments repeatedly after being discharged too soon from psychiatric wards.
He said better management in recent years meant fewer were staying on emergency wards longer than a day or two, but they needed to be assessed and transferred within one or two hours.
"There's no doubt we are very short of acute, sub-acute and community beds and resources at all levels of our system and we need to improve capacity to actually deal with patients in a much more co-ordinated way to make sure people do not fall through the gaps," he said.
Arafmi Mental Health Carers and Friends Association director Mike Seward said admissions would be reduced if mental health professionals listened more to patients and carers.
They could often flag a patient was going downhill and needed intervention but found it hard to get the system to take heed.
WA Mental Health Minister Helen Morton said she would look into setting up a trial mental health emergency department at a WA hospital.
Shadow minister Ljiljanna Ravlich said mentally ill people went to emergency departments because there was nowhere else to go, which was a sad reflection on the State Government.
Emma, who did not want her surname used, said her 40-year-old husband spent four days in and out of emergency wards this week after a "psychotic episode" before being sent home.
"I'm shocked. Less than 24 hours after I saw four people holding him down they wanted me to take him home," she said. "That's not what a normal person would consider right."
He was given medication for a few days and an appointment to a psychiatrist for a week after he went to the hospital.