The Tower Bridge Care Home at Bricklayers Arms has been rated as 'inadequate' by the Care Quality Commission (CQC) after an unannounced inspection in August.
The care home – at the junction of Tower Bridge Road and Old Kent Road – has more than 100 residents, including people living with dementia. It is owned and run by the HC-One company.
The CQC report was published this week and concluded that residents "were not safe and were at risk of avoidable harm" and that there were "widespread and significant shortfalls in service leadership".
Inspectors found "significant and widespread issues with the ordering, storage and administration of people's medicines" including staff carrying out tasks they were not trained for, missed doses of medication, expired medications being given to residents and more than one resident being given medicine from the same tub, rather than their individually prescribed supply.
The CQC also noted that "there were not enough staff to meet people's needs" and that "staff appeared to be tired and rushed and people appeared unkempt".
"For example, we saw numerous people wearing stained clothing."
The report also found failures in management: "The provider did not promote a positive culture that was achieving good outcomes for people. Staff told us they felt under-appreciated and sometimes overworked."
A spokesperson for HC-One told the SE1 website: “Our top priority is to deliver high quality, kind care for each of our residents, and we take all feedback from the regulator extremely seriously.
"We acknowledge that in the past we have fallen short of the high standards our residents and their loved ones rightfully expect and deserve, and apologise for this."
The company said that a "new, experienced manager" is now in place at Tower Bridge Care Home and that improvements have already been made.
HC-One added: We are working closely with the local authority and the CQC to embed positive changes at the home, and we will continue to monitor the quality of care using our own internal assessments.
"We know there is still work to do to put things right, but everyone is determined to make and maintain the improvements needed to ensure we deliver high-quality, kind care at the high standards to which we hold ourselves."