Marquis Court (Tudor House) care home in Littleworth Road, Hednesford, has been rated 'inadequate' and placed in special measures following an inspection by the Care Quality Commission in November and December.
Inspectors found a string of failings, including people not receiving the support they required around mealtimes, pressure care and wound care, according to a CQC report.
It resulted in people losing weight and the condition of their skin deteriorating.
The care home, which is run by Four Seasons Homes No.4 Limited, provides nursing and personal care for up to 52 adults.
But the provider said it is following an action plan to address the issues highlighted by the health watchdog.
A spokesperson for Four Seasons said: “We deeply regret that Tudor House Care Home is below the standards that we and the Care Quality Commission expect.
"Since the inspection in November, we have implemented a comprehensive action plan to address the areas noted in the report and its execution is being overseen by our managing director and regional management.
"We have recruited new team members to support residents in the home. We have also audited all care plans, reviewed team deployment, improved processes around communication, dining and activities, and provided additional training to colleagues since the inspection.
"The safety and wellbeing of residents and colleagues in our homes remain our first priority.”
Inspectors said they found a repeated breach of regulations in relation to governance and oversight at the care home, which had previously been rated as 'requires improvement' overall.
The CQC said there were also further breaches regarding people's safe care and treatment, person-centred care, nutrition and hydration care and staffing issues.
Amanda Lyndon, CQC head of hospital inspection for adult social care, said: “When we inspected Marquis Court (Tudor House) care home, we found widespread and significant shortfalls within leadership which was impacting on people’s care.
“This service has been rated as 'requires improvement' at its last nine inspections, and despite us telling leaders very clearly, where they needed to improve, there has been little to no progress against previous breaches in regulation, and now we’ve seen a decline in the quality of care being provided with further breaches.
“Leaders weren’t managing the service well, and staff didn’t have a clear consistent understanding about quality performance requirements and risks. For example, the management team had completed an action plan to address concerns they had found.
"However, this had failed to identify and take immediate action to deal with the concerns we found during our inspection. This placed people at a continued risk of harm.
“There wasn’t enough staff to ensure people's basic care needs were being met in a timely way.
"We were told of times where people didn’t have support with personal care until midday or later, which is totally unacceptable. Also, people weren’t able to have a shower when they wished to, with one staff member telling us that they were only able to support people to shower once a week because they didn’t have enough time to do more.
“Where people had experienced weight loss, staff had referred them to external agencies for review and further support.
"However, staff weren’t consistently providing people with the support external agencies recommended. For example, one person had a pureed diet due to risk of choking and required staff to observe them at mealtimes - however they did not receive this, which placed them at an increased risk of choking.
“We will continue to monitor the service closely to ensure people are safe and improvements have been made and embedded. If we are not assured people are receiving safe care, we will not hesitate to take further action.”