The Ministry of Health is urging people in Otago and Southland who may have been treated by a doctor working illegally to contact their GP.
Dr Sajan Bhatia has been found to have worked in Invercargill without the proper practising certificate.
The urologist operated from a premises in Dee Street without a certificate since February 2007.
The Ministry says the Medical Council did not renew Dr Bhatia's annual certificate in December 2008, because he did not comply with his conditions of practice.
That followed findings of professional misconduct by the Health Practitioners Disciplinary Tribunal in February 2007 in relation to his treatment of a Southland woman in 2004.
After the tribunal's finding the council applied conditions to Dr Bhatia's practice, including regular peer reviews, an audit of his patient outcomes, and a requirement that he work under the supervision of another urologist.
Bhatia was not able to demonstrate to the council that the conditions were satisfactorily met and, in December 2008, it did not renew his certificate.
People who were seen by him since 2007 are advised to have their care reviewed.
