Pomersbach only played one T20 for Australia in 2007 but his hard-hitting exploits earned him contracts with the Kings XI Punjab and Royal Challengers Bangalore in the Indian Premier League.
He has most recently been playing for the Queensland Bulls and Brisbane Heat.
"We appreciate the difficulties and challenges that Luke faces with his illness," said Queensland Cricket chief Geoff Cockerill.
"The most important thing is that Luke continues to receive the necessary treatment and has the best possible support available to him.
Pomersbach, 29, had a history of off-field misdemeanours. He said he appreciated the support he had been given by Queensland Cricket and his teammates over the years.
"Especially over the past couple of months leading up to this difficult decision to leave professional cricket so that I can put all my efforts into getting better and making a full recovery," he said.