Inspectors also discovered pensioners at Nithsdale House were bored, going to bed hungry and missing out on showers. Actions taken in response to weight loss were described as "inadequate".
The home, which is owned by Lotus Senior Living Ltd, has been told to make urgent improvements after being given the lowest possible care grading by the Care Inspectorate.
Inspectors found incontinence pads in bins without liners, dirty tables where residents ate meals and poor practice in administering medication.
They also found cleaning fluids not locked away, posing a potential risk to people with dementia, and staffing levels were said to be inadequate.
Comments from residents included: "I've been waiting to get out of here. No-one's been to see me. I get bored here."
Two of the five senior carers were not registered at supervisor level with the Scottish Social Services Council (SSSC) which is a requirement of the role.
A report on the inspection, which was carried out on February 18, said areas for improvement were identified across all quality themes inspected.
Inspectors also noted that there had been "very little progress" following an earlier inspection which had highlighted concerns.
A spokesman for the Care Inspectorate said: "Whilst we noted some improvement in some areas following a previous inspection, significant concerns remain over the service's performance in relation to ensuring health and wellbeing of residents.
"If we are not satisfied improvement is being made we will not hesitate to take further action."
In another report, Drumpellier Lodge in Bargeddie received the second lowest rating in three areas examined.