Kirkcowan Community Council member John Paterson branded the new layout "very dangerous" at last week's Wigtown Area Committee meeting in Stranraer.
He told councillors that there should be a slip road into the hospital off the A75 to allow motorists to decelerate safely.
He told concerned councillors he had recently witnessed a car turning off to the hospital and the car behind it having to "take across to the other side" to avoid a collision. He also condemned the planners for the lack of a bus stop nearby. He said: "Passengers visiting the hospital are having to either go to Dashwood Square and walk back up or get off at Barnkirk or Georgewell Drive and walk down the A75 - where there is no pavement - to get there."
Wigtown West Councillor Robert Higgins said that the area committee should report the matter to the council's Planning, Housing and Environment Committee, adding: "The Scottish Government designed it."
Mid Galloway Councillor Sandra McDowall said she had "grave concerns" about the new road layout for the overtaking lane around the time of the planning stage but she said they were told at public meetings by the designers that "it would be engineered out".
"This has obviously not happened," she added. The subject was revisited at Monday night's Cree Valley Community Council meeting, which was attended by Galloway MP Russell Brown.
After hearing the concerns about safety, Mr Brown commented: "I got the feeling from this community that they were never happy with the new road layout."
Asked how much the overtaking scheme had cost, the MP replied: "About £3 million."
After the meeting, area committee chairman Graham Nicol said: "I always thought that there was going to be a slip lane there.
"It's a piece of nonsense that there isn't, as there is certainly enough room.
"I will be lobbying heavily to have it instated."