Patient information · Dermatology
Fungal skin and nail infections
why treatment so often fails
Athlete's foot, ringworm, groin infection and fungal nails are all caused by the same family of fungi. They are easy to treat and very easy to treat inadequately — the usual failure is stopping when the skin looks better rather than when the fungus has actually gone.
Seek prompt assessment if there is
- spreading redness, heat and pain around the affected skin, or a fever
- fungal infection in someone with diabetes, particularly on the feet
- a weakened immune system, or you are on immunosuppressive treatment
- widespread or rapidly spreading rash
- scalp involvement in a child — this needs oral treatment, not cream
Cracked skin between the toes is one of the commonest entry points for cellulitis, particularly in people with diabetes or leg swelling. Treating athlete's foot is genuinely preventive rather than cosmetic.
The main types
- Athlete's foot — itchy, scaly, cracked skin between the toes, or a dry scaling pattern across the sole.
- Ringworm — a spreading ring with a raised, scaly edge and clearer centre. Nothing to do with worms.
- Jock itch — an itchy red rash in the groin creases, usually spreading outwards, typically sparing the scrotum.
- Fungal nail — thickened, crumbling, yellow-white or brown nails, often starting at the outer edge.
- Scalp ringworm — scaly patches with hair loss in children. Creams do not work; oral treatment is required.
Treating skin infections properly
- Use an antifungal cream such as terbinafine, clotrimazole or miconazole from a pharmacy.
- Apply beyond the visible edge — a couple of centimetres of apparently normal skin around it, where the fungus already is.
- Continue for one to two weeks after the skin looks normal. This is the step almost everyone skips, and the reason it comes back.
- Treat both feet even if only one looks affected, and treat the groin and feet together — groin infection usually comes from the feet via a towel or underwear.
- Keep the area dry. Dry between the toes thoroughly, change socks daily, alternate shoes so each pair dries out, and dry the groin before dressing.
Combined steroid and antifungal creams are frequently the wrong choice
Products containing both a steroid and an antifungal are widely used for itchy rashes. On a fungal infection the steroid suppresses the inflammation, making the rash look better while the fungus spreads — producing an atypical, extensive infection that is much harder to recognise and treat. If a rash has been treated with a steroid cream and behaved oddly, mention it; the diagnosis may need reconsidering with a skin scraping.
Fungal nails
Nail infection is much harder to clear than skin infection, and it is worth confirming with a nail clipping sent for testing before committing to months of treatment — around half of thickened, discoloured nails are not fungal at all.
- Nail paints may work for early infection affecting the outer part of one or two nails, applied for six to twelve months.
- Oral terbinafine is considerably more effective and is usually needed for anything more than mild disease — typically three months for toenails, with liver function checked.
- The nail will not look normal immediately. It grows out slowly: fingernails take six months, toenails twelve to eighteen. Judge success by the new growth at the base, not the old nail.
- Treat the accompanying athlete's foot at the same time, or the nails will simply be reinfected.
Preventing recurrence
- Wear flip-flops in communal showers, changing rooms and around pools.
- Do not share towels, socks, shoes or nail clippers.
- Wash socks and towels at 60°C.
- Consider an antifungal powder in shoes if you are prone to recurrence.
- Treat the household pet if a child has ringworm — cats and guinea pigs are common sources.
Book an appointment if a rash is not clearing after two weeks of treatment, you have diabetes with a foot infection, a child has scalp involvement, or you want nails tested before starting tablets. We can take samples for laboratory confirmation and prescribe oral treatment with monitoring.
Sampling, diagnosis and oral treatment
Seven days a week, 9am–7pm, on Whitechapel Road.
Tower Bridge Hospital London
97–99 Whitechapel Road, London E1 1DT
WhatsApp 07903 284 189
info@mhwclinic.co.uk
Open Mon–Sat, 9am–7pm (closed Sundays until September)
In an emergency
Call 999, or go to the Royal London Hospital Emergency Department, Whitechapel Road, London E1 1FR.
When we are closed and it is not an emergency
Call NHS 111 or visit 111.nhs.uk.