Alberta Health and Wellness Minister Gene Zwozdesky ordered homosexuality to be removed from a provincial diagnostic guide of mental disorders. (CBC)

Alberta has removed homosexuality from its diagnostic guide to mental-health disorders.

Alberta Health and Wellness Minister Gene Zwozdesky ordered the section of the document removed Tuesday after a reporter brought the issue to the province's attention.

"I ordered the immediate removal of something I thought was incorrect, unacceptable, rather ancient in its thinking and otherwise demeaning," he said Wednesday.

"I've also asked for a thorough review of the entire classification categories."

The diagnostic guide helps doctors decide what to bill for the treatment of patients.

Homosexuality was listed in the guide under sexual deviations and disorders.

The American Psychiatric Association stopped considering homosexuality a disorder in 1973, followed by the Canadian Psychiatric Association in 1982.

Zwozdesky said he doesn't know why it remained so long on Alberta's list.

However, members of Edmonton's gay community said the government has long shown half-hearted support for gay rights in the province.

"People who are gay and lesbian like myself have had to fight every step of the way to make any changes at the political level," said former city councillor Michael Phair. "I wonder whether this was forgotten or ignored."

Albertans are more progressive in their attitudes about gay rights than their government, he said.

The province promised twice to remove the section over the last dozen years and failed to do so on both occasions, said Liberal MLA Laurie Blakeman.

"Frankly, it just couldn't be bothered to make the changes," she said.