Tristar Medical Group's director of clinical operations Anne Gardner said a senior doctor at Murtoa, Minyip and Rupanyup clinics had left the region.

"He has relocated to Melbourne," she said.

Ms Gardner said Tristar had been unable to recruit another GP to replace the doctor because of ongoing financial pressures.

"One of our very dedicated doctors from Horsham continues to provide nursing home and on-call support until we can source another long term option," she said.

"All Tristar existing bulk-billed services currently operating in the Wimmera will continue now and into the foreseeable future under Tristar's restructured business model."

Ms Gardner said changes to government regulations and the ongoing Medicare freeze was making it difficult health services across regional Victoria to continue.

"There have been large numbers of medical practices close across the nation in regional and remote Australia due to the impacts of skilled migration policy changes and an economically non-viable regulatory process for doctors' training pathways in general practice," she said.

"Policy changes were implemented without consultation with GPs or industry stakeholders."

Ms Gardner said the restrictions was also affecting doctor recruitment in the region.

"On numerous occasions this has led to entire communities being left with no doctor in their town," she said.

"The non-consultative policy change process over the past few years; and the extended Medicare freeze has had unintended consequences across our entire primary health care system."

As a result of the challenges, Tristar Medical Group has gone through a restructure process.

Ms Gardner said Tristar had closed more than 15 practices across Victoria, NSW and South Australia in the past 18 months.

She said none had closed in the Wimmera, though it had transferred the practices at Jeparit and Rainbow, where one GP offered services out of buildings in both communities, to another service provider.

Tristar also has clinics at Horsham, Nhill, Ararat, Warracknabeal, Kaniva and Goroke.

Ms Gardner said Tristar doctors in the region remained committed to their patients.

"The bulk of GP contractors have continued to work with Tristar during our restructure period; and have voiced their ongoing support to try to retain a universal primary health care system; and a sustainable bulk billing service in communities of need," she said.

"We are aware that each time a community reads or hears another news article reporting the same issue with regards to the financial challenges facing Tristar; this evokes concerns among its members and a real worry that they might be left without medical services.

"We plan to fight to retain services in our communities and for families where ever we can."