The poster for PatientPak claimed that the pack, which includes 'essential comfort items to offer you the best protection', was 'the first ever kit developed specifically to help keep you safe, clean and free from superbugs, viruses and bacteria'.
However, the Advertising Standards Authority (ASA) was alerted to the adverts after it received complaints from the public believing they were 'playing on consumers' fears'.
The poster, which advised patients going into hospital, pregnant women and the elderly that the PatientPak was 'essential' for their well-being, ran for 10 days but it has now been removed.
The makers of PatientPak have changed the poster and amended the wording in time for the second advertising campaign - a move which the ASA has welcomed.
The ASA ruling states: 'We considered that the claim 'essential for your well-being' implied that without the pack, hospital patients, pregnant women and the elderly were at risk from contracting a superbug or virus.
'We therefore concluded that the poster was likely to mislead and played on people's fears.'
RCN general secretary Peter Carter said: 'It is irresponsible and potentially dangerous for PatientPak to even suggest that their product will do anything to tackle healthcare associated infections.
'In our view, this product does not act in the interests of patients, but adds to the swathe of misinformation on infections and plays on public anxiety,' he added.
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