What is it like to have to wait in hospital for hours for appropriate mental health attention?

The way Hobart man Gary describes it, the experience is a nightmare.

He is one of many people who have presented at Royal Hobart Hospital in need of mental health treatment only to have had to wait up to three days for a bed in the mental health ward.

The delay is due to the reduced capacity of the Royal's mental health ward as the hospital undergoes redevelopment.

So until a bed becomes available, these patients have to wait in the emergency department.

Last November, Tasmanian coroner Simon Cooper stressed the unsuitability of this arrangement, saying it contributed to a man's death.

"The department of emergency medicine at the Royal Hobart Hospital is no place for anyone suffering from depression, anxiety suicidal ideation and indeed any mental health issue," he said.

"You get paranoid about people looking at you, even when they're not," says Gary. ( ABC News: Scott Ross )

Gary, who has a terminal illness that has had a profound impact on his mental health, knows this only too well.

"I've been in at different times, with all sorts of thoughts about doing self harm," he said.

During his most recent presentation to the ED three months ago, Gary spent 19 hours in a chair waiting for a bed on the psychiatric ward.

"It's a really horrible feeling," he said.

"I left there worse than I went in. I was a mess."

The lack of privacy was confronting, he said.

"You're interviewed like you're in a cell where everyone can hear what the doctor's saying," he said.

"I just felt violated because everybody knew that I was this nutcase."

Gary is a slight man with a piercing gaze.

The confidence he speaks with is in stark contrast to the picture he paints of himself as a mental health patient.

"You get paranoid about people looking at you, even when they're not," he said.

"There's all this noise going on in the background and all you want to do is be left alone and try to cope with what you're going through."

It's not the only time Gary has spent hours waiting in the ED for a bed on the psychiatric ward.

Several years ago, he was taken to the ED by police after threatening self harm.

He waited a day and a half for a bed.

"I honestly felt at that stage it would be less painful for me going and getting hit by a bus," he said.

"My thought pattern went from, 'Maybe I'll get some help' to no hope."

"'Would you shut the noise up? Would you stop the bells from ringing? I can't handle this' ... I got up and walked out."

Anxiety and isolation compounded

This week five patients needing a mental health bed waited for two days. ( ABC News )

As recently as Tuesday morning this week, it is understood five mental health patients were waiting for a bed.

Some had already been waiting 40 hours and they were not admitted until the late afternoon.

Australian Medical Association mental health spokesman Dr Richard Benjamin has previously warned about potential "adverse outcomes".

"Patient areas are small and it's a noisy, high-stimulus environment with no access to natural light, big enough or therapeutic enough spaces, or the outdoors," he said.

"We know that our patients don't do well there — they often get more agitated and want to leave, and they are often exposed to more medication."

For Gary, the ED only compounded his anxiety and sense of isolation.

"Thoughts that nobody cares, and I feel like I'm really losing the plot," he said.

"You've got your own thought patterns going on, you've got buzzers going off, you've got people talking; they're moving around like you're not there.

"It's almost like when an alarm clock goes off — you wish you could just shut it off by smashing it."