National Patient Safety Alert: Inadvertent oral administration of potassium permanganate

Summary

Potassium permanganate is routinely used in the NHS as a dilute solution to treat weeping and blistering skin conditions, such as acute  weeping/infected eczema and leg ulcers. It is not licensed as a medicine.

Supplied in concentrated forms, either as a ‘tablet’ or a solution, it  requires dilution before it is used as a soak or in the bath. These concentrated forms resemble an oral tablet or juice drink and if ingested are highly toxic; causing rapid swelling and bleeding of the lips and
tongue, gross oropharyngeal oedema, local tissue necrosis, stridor, and gastrointestinal ulceration. Ingestion can be fatal due to gastrointestinal
haemorrhage, acute respiratory distress syndrome and/or multiorgan failure. Even dilute solutions can be toxic if swallowed.

A Patient Safety Alert issued in 20142 highlighted incidents where patients had inadvertently ingested the concentrated form, and the risks in relation to terminology and presenting tablets or solution in receptacles that imply they are for oral ingestion, such as plastic cups or jugs.

A review of the National Reporting and Learning System over a two-year period identified that incidents of ingestion are still occurring. One  report described an older patient dying from aspiration pneumonia and extensive laryngeal swelling after ingesting potassium permanganate tablets left by her bedside. Review of the other 34 incidents identified key themes:

• healthcare staff administering potassium permanganate orally
• patients taking potassium permanganate orally at home, or when left on a bedside locker
• potassium permanganate incorrectly prescribed as oral medication.

The British Association of Dermatologists (BAD) ‘Recommendations to minimise risk of harm from potassium permanganate soaks’ includes advice on formulary management, prescribing, dispensing, storage, preparation and use, and waste.

Actions

Actions to be completed by 04 Oct 2022:

1. Review the overall use of potassium permanganate at trust/area drug and therapeutics committee to consider if the benefit outweighs the risk.

2. Unless eliminating the use within the trust/locality, ensure procedures/guidelines for use of potassium permanganate align with all BAD recommendations, including:

a) In primary care:

• patients are not on repeat prescriptions for potassium permanganate
• prescriptions include clear instructions to dilute before use
• dispensing label includes the warning ‘HARMFUL IF SWALLOWED’.

b) In secondary care:

• remove all stock supply (except for use within outpatient departments) and supply on a named patient basis only
• potassium permanganate is prescribed as ‘potassium permanganate 0.01% topical solution’ and the dispensing label must include the warning ‘HARMFUL IF SWALLOWED’
• potassium permanganate is not stored with medicines for oral/internal use, including the ward drug trolley; dilution should occur away from the patient, and neither the concentrated form or the diluted form, should be left near the patient.

c) All settings:

• prescriptions are only issued by an appropriate prescriber – see recommendations
• if potassium permanganate is to be used in a patient’s home, a risk assessment must be undertaken before prescribing
• all patients must be supplied with a patient information leaflet.