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Wrong strength phenol | Signal

Reference number
1162 D
Issue date26 February 2010

This Signal relates to confusion of different strength phenol, resulting in severe harm to a child when a high-strength product is injected in error.


Phenol is an antibacterial drug which comes in different forms. The main types are 80% aqueous (liquefied) phenol used topically in podiatry for removal of ingrown toenails; 5% oily phenol injection, used in treatment of haemorrhoids, and other low strength forms used for pain relief and to control spasticity. Confusion between different strength and preparations of phenol has resulted in patient harm.


A sample incident reads:
“Patient was injected with liquefied phenol (80%) into the rectal submucosa instead of oily phenol (5%). Patient suffered severe tissue loss needing further emergency surgery, but survived.”


The National Reporting and Learning Service (NRLS) was alerted by a trigger incident at one trust where a child suffered severe harm following confusion between different forms of phenol. NRLS found six more incidents on the Reporting and Learning System (RLS) database that related to confusion between different forms of phenol.

Further learning was obtained from thorough local investigations at the two trusts where patients had been harmed. One key contributing factor was that liquefied phenol is rarely used (only used three times in last six months in one reporting unit) and so staff were not familiar with the product and unaware that it came in different forms. Local actions included removal of high strength liquefied phenol from all clinical areas and replacing it with safer alternatives (unit dose swabs).

Other work by NRLS has focused on the design of labelling and packaging to prevent errors. NRLS has raised this issue with manufacturers and will be pursuing this for changes to reduce risk of confusion.

Could this happen at your organisation?
Is there scope for confusion in different forms of phenol stocked in theatre (and could alternative products be used for haemorrhoids)?


Relevant to: Medication, surgery



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