Red flags and when to refer

If a person with a fungal nail infection presents with the following symptoms, advise them to see a GP:

• You suspect melanoma. Occasionally, a fungal nail infection can appear black-brown. In a fungal infection, the discolouration tends to start at the top of the nail, whereas the most common presentation of melanoma is a line growing continuously from the bottom of the nail⁴
• There are signs of a more severe infection, including fever, increased redness, swelling, pus-filled blisters and spread of the infection to other nails or skin areas
• Over-the-counter treatments aren’t working
• The infection is severe or reoccurring
• Other skin conditions are present
• The person is immunocompromised.⁵