The confirmation comes as authorities in the UK move to carry out urgent checks on the credentials of up to 3000 foreign doctors working in Britain.
The move was sparked after Alemi, who is said to be an Iranian-Kiwi, was last month jailed for five years after it was found she had provided false qualifications that allowed her to work as a psychiatrist for 22 years.
She worked as a doctor up until June of last year.
The 56-year-old, who moved to the UK in the early 1990s, claimed to have a degree from the University of Auckland.
She reportedly provided bosses with a Bachelor of Medicine and a Bachelor of Surgery certificate from the university.
No one at the General Medical Council - the watchdog responsible for vetting the background of medics - checked the documentation to ensure it was genuine.
She would only be found out more than two decades later when she tried to fraudulently alter an elderly patient's will.
Had she been successful, Alemi would have stolen up £1.3 million ($2.4m) of the woman's fortune.
For the next 22 years, starting in 1995, Alemi worked as a psychiatrist for the UK's National Health Service - treating thousands of mental health patients over that period and potentially earning up to £100,000 ($188,000) a year.
She also drove a Lotus Elise sports car, the Daily Mail reported.
In a since deleted profile, Alemi says of herself: "I am a retired psychiatrist and a member of the London Royal College of Psychiatrists with a special interest in developmental conditions such as Asperger's ...''
The GMC is now informing Alemi's former patients who may have concerns about their treatment to contact their GP doctor immediately.
Chief executive for the council, Charlie Massey, said staff immediately brought the situation to the attention of police and other agencies when they found Alemi's fraudulent qualifications.
"Our processes are far stronger now, with rigorous testing in place to ensure those joining the register are fit to work in the UK.
"It is clear that in this case the steps taken in the 1990s were inadequate and we apologise for any risk arising to patients as a result," he said.
"We are confident that, 23 years on, our systems are robust and would identify any fraudulent attempt to join the medical register."
