Miltongrange nursing home in Carluke, South Lanarkshire, was inspected by regulators after issues were raised.
The Care Inspectorate has now served a formal improvement notice listing seven areas of concern which it said must be improved upon quickly. If not, it could lose its registration as a care home.
Staff training, management and infection control were also areas highlighted by inspectors, who will return to the care home over the next few months to check on progress.
Miltongrange specialises in care for elderly people with Parkinson's disease, who have suffered strokes, or have hearing, speech or visual impairments.
A spokesman for the Care Inspectorate said: "We were concerned about the way in which the needs of residents were being met, including concerns about skin care and nutrition.
"We were also concerned by poor infection control procedures; staff training; staff skills and competencies; notification reporting; and the quality of management and leadership.
"Everyone in Scotland has the right to safe, compassionate care which meets their needs and respects their rights.
"Where we have concerns we do not hesitate to take action.
"Our first priority is always the safety and well-being of residents and this improvement notice sets out what we expect the service to do to ensure that the care provided to residents improves.
"We will be inspecting this service again soon to ensure that progress is being made."