Ambulances have been called to the Star Casino in Sydney 173 times a year on average since 2011, with suicide attempts and overdoses among the reasons, freedom of information (FOI) documents show.

The data, obtained by ABC News from NSW Ambulance, shows in the past five years, paramedics were dispatched to the casino 48 times for abnormal and psychiatric behaviour, including attempted suicide, and 117 times for overdose or poisoning by ingestion.

Former Star Casino games dealer Sarah Sherwood alleged the 24-hour casino in the harbour-side suburb of Pyrmont pressured staff to encourage gamblers to continue betting, even if they showed signs of problem gambling.

"They don't really focus on that sort of thing," she said.

"They'll do a quick seminar every now and then, but they generally want you to just have fantastic customer service skills.

"They want you to encourage people to play."

Ms Sherwood said the ambulance data reflected behaviour she often saw in customers while working there.

"People there who can't afford [it] … They lose everything," she said.

Suicide risk highest after large loss: psychologist

Clinical psychologist at the University of Sydney gambling treatment clinic, Dr Christopher Hunt, said problem gambling could often lead to suicidal thoughts and attempted suicide.

"When people are most at risk of having suicidal thoughts or making a suicide attempt is after a large loss — particularly if they're at a desperate point in their life," Dr Hunt said.

He said problem gamblers could be hard to immediately identify at a venue like a casino, and their behaviour could go undetected.

"A lot of people say: 'At the venue, it should be obvious who is the problem gambler'," Dr Hunt said.

"But it's not just about the money loss. It's about the money loss relative to someone's income.

"So it can be difficult to identify just by saying: 'This person's lost a lot of money'."

Erratic, desperate behaviour 'a common sight'

But Ms Sherwood said gamblers displaying erratic or desperate behaviours were a common sight at the casino.

Ms Sherwood said the ambulance data reflects behaviour she often saw in the casino's customers. ( Destination NSW )

"They're irritable, they get angry over nothing," she said.

"They blame the dealer a lot. They even get in arguments with the other players.

"They will be very antisocial in the way where they don't speak to anyone, they won't get up from the table.

"There have been cases of dealers being peed on. People actually … have [a bag] attached to them so they can just pee themselves at the table and don't have to get up to go to the bathroom.

"Because they don't want to lose their seat, they don't want to lose a good run."

'They just don't care'

While there are procedures in place to report such behaviour among gamblers to supervisors, Ms Sherwood said they were rarely followed through.

"They say if someone's intoxicated, you must tell your supervisor and they will be asked to leave, but quite often that doesn't happen. They just generally don't care," she said.

Ms Sherwood said the casino's rules do not go far enough.

"You cannot exclude someone for problem gambling. They have to self-exclude," she said.

"Because obviously they don't want to lose a player that gives them so much money.

"They just basically want to avoid trouble at all costs."

Dr Hunt said even though casinos could be dangerous at times as they were often designed to keep customers gambling, casino managers did not bear sole responsibility in curbing problem gambling among their customers.

In a statement, a Star Casino spokesperson rejected Ms Sherwood's allegations and said the safety of its guests was a priority.

"The Star has a higher level of oversight and regulation than any other licensed venue in NSW. On problem gambling, we go well beyond our legislative requirements."

The spokesman also said The Star works closely with the NSW Police and the casino regulator to mitigate anti-social behaviour.