MICHAEL COSTA, widely regarded as the most eccentric man in the NSW Parliament, has revealed he has had to act as a counsellor to some of his parliamentary colleagues who have come to him about their mental health problems.

Mr Costa, who has bipolar disorder, told the Black Dog Institute yesterday that although he now managed his own mental illness with medication, he knew of many politicians who suffered similar mood disorders but were unwilling to seek help.

"People are very reluctant in political life to come forward with their issues relating to mood disorders," Mr Costa said.

"The reason for that is politics is a contact sport with lots of aggression, and in arguments, of course, there is a temptation too great to use any weakness as part of an argument around policy issues."

Mr Costa said opponents to his stance on electricity privatisation in NSW had used his bipolar disorder against him. "I noted my views on this were characterised as being a function of my manic depression," he said.

"You talk about stigmatism … we have a long way to go, particularly in the realms of politics."

Mr Costa said his family had a history of mental illness. His sister was schizophrenic and his mother also suffered from bipolar disorder.

He said he wished more well-known people would open up about their condition to help abolish the stigma of mental illness.

"There is a tendency for many people to misassociate mood disorder with intellectual impairment, and I find that incredibly frustrating," Mr Costa said.

The Treasurer was launching Managing Bipolar Disorder , which is a collection of case studies and diary entries from people with bipolar disorder, edited by the psychologist Kerrie Eyers and the University of NSW psychiatry professor, Gordon Parker.