A dementia care home has been placed under special measures by a watchdog, after breaches were found during an inspection, including medicines being cross-contaminated.
Westminster City Council is working with two local nursing homes after the Care Quality Commission (CQC) found breaches in their services following inspections.
St George's Nursing Home, in St George's Square, received a particularly unfavourable rating in the latest round of inspections.
The independent nursing and dementia care home has been placed in special measures by the CQC over safety issues, including not measuring out medicines correctly.
The home caters to 32 people, including 20 living with dementia.
The CQC's report said during an inspection in August last year, an inspector found breaches of service, including safety.
St George's was asked to make an action plan to improve its practices, but the CQC found issues at its re-inspection this April.
Its report said inspectors found people were missing their medicines, receiving the wrong dose or at the wrong time - and tablets were being crushed in a dirty container, contaminated by other medicines.
The report said the poor management of medicines led to one person receiving an ear drop in their eye.
It found 35 medicine-related incidents or errors recorded in the 13 weeks leading to the inspection.
It also found staff were not being adequately screened during recruitment, and lacked formal training for issues such as infection control; although the building was noted to be clean.
While action had been taken to improve safety risk prevention, such as from bedsores or choking, the inspectors found the home failed to take action to prevent recurrences.
It also faulted the home for its dementia patient treatment, finding there was a lack of meaningful activities for them, with the inspectors commenting that the building was poorly laid out for people living with the condition.
While people and their families at the home told inspectors they felt safe using the service, the CQC found multiple breaches, and placed St George's under special measures.
Elderly people's home Vincentian Care Plus (VCP) also received an "inadequate" rating following an inspection last August, over safety and leadership issues.
The latest inspection results for the home are not yet available online.
However, Westminster's Family and People Services Policy and Scrutiny Committee's papers this week showed a new manager was appointed by VCP in May, after the council and CQC recommended the change in leadership.
Council minutes show between April 1, 2017 and January 31, 2018, the CQC had inspected 88 services in Westminster, of which five locations had been rated 'outstanding'; 58 were 'good'; 23 'required improvement' and two were rated 'inadequate'.
That compared to about 7 per cent of care providers in London rated as 'requiring improvement', or 'inadequate'.
Westminster formed a new quality assurance team this March, to focus on helping its care providers improving their services.
Its Cabinet Member for Family Services and Public Health, Cllr Heather Acton, said council teams would work closely with the CQC and the management of any provider that failed to meet its standards.
"Our elderly and vulnerable residents deserve the best possible residential, nursing and domiciliary care and it is never acceptable for care to fall below regulatory standards," she said.
"Westminster City Council is determined that every care facility in the borough acquires a 'good' or 'outstanding' rating from the Care Quality Commission."
Both St George's Nursing Home and VCP were asked for comment on their CQC ratings.