Fungal Skin Infection
Diagnosis and treatment of fungal infections affecting the skin, nails or scalp
What is fungal skin infection?
A fungal skin infection is caused by organisms that feed on keratin, the protein in the outer layer of skin, in the nails and in hair. They grow outwards from where they take hold, so the edge of a patch is usually more active than its centre.
They need warmth and moisture, so the groin, the feet, the skin folds and under the breasts are the usual sites, and an Indian summer, long hours in closed shoes, synthetic clothing and shared towels all help them along. They pass between people, from pets, and from one part of your own body to another on your hands.
Infections in India have become noticeably harder to clear over the last decade. A large part of that is the combination creams sold over the counter that contain a strong steroid: they calm the itch for a week, alter the appearance so the diagnosis is harder, and let the fungus spread further and deeper.
What you might notice
- An itchy ring-shaped rash
- Itchy dry patches of skin
How it is diagnosed
Your doctor recognises most fungal infections by looking: the shape of the patch, the raised active edge, the pattern of spread, and whether the nails, the groin and the feet are involved together, since one site seeds another.
They will ask what you have already applied, and this question matters more than any other. A patch treated with a steroid-containing cream looks different, spreads wider and has less of a defined edge, so bring the tube with you to the appointment.
Where the picture is unclear or the infection has resisted treatment, a scraping of skin or a clipping of nail is examined under a microscope and sent for culture. Nails in particular are confirmed before a long course of tablets is started, since not every thickened nail is fungal.
Recovery
Skin infections clear over two to four weeks of correct treatment, and the cream is continued for a week or two after the skin looks normal, since the fungus outlasts the appearance. Deep or widespread infection needs tablets for several weeks.
The scalp and the nails run much longer. Scalp infection needs weeks of tablets, and nails need months: roughly three to six for fingernails and nine to twelve for toenails, and even then the nail only looks normal as the healthy part grows out, so judging success before then is misleading.
You are not infectious in a way that requires staying home, and there is no time off work. The habits carry the result: keep the area dry, change socks and underclothes daily, use your own towel, dry the feet and the folds properly, and treat everyone in the household who has it at the same time.
If it is left untreated
A small patch occasionally settles on its own once the skin is kept dry, though most do not.
Left alone, the patch enlarges and spreads to the groin, the buttocks, the trunk and the hands, and it passes to the people who share your bed and your towels. Nails that become involved thicken, crumble and lift from the nail bed, and nail infection is far harder to treat than skin infection, so treating the skin early avoids a course of tablets months long.
Skin broken by scratching lets bacteria in, and that matters most in people with diabetes or poor circulation, where an infection between the toes can become a much bigger problem. Widespread, steroid-modified infection that has failed several treatments needs specialist care instead of another tube from the pharmacy.
Questions about fungal skin infection
Why does it keep coming back?
Recurrence usually has one of four causes. The treatment was stopped when the skin looked clear instead of a week or two later, so surviving fungus regrew. Another site on your body, most often the feet or the nails, was never treated and reseeded the skin. Someone else in the house has it and you are passing it between you. Or the conditions have not changed: damp folds, closed shoes all day, shared towels, synthetic clothing. Your doctor will go through all four, and fixing them matters as much as the medicine.
Are the combination creams from the pharmacy a problem?
They are the single biggest reason fungal infections in India have become hard to treat. Most contain a strong steroid alongside an antifungal, and the steroid removes the itch and the redness within days, so they feel effective. Underneath, the fungus spreads further and deeper, the patch loses its typical appearance, and the skin thins. Infections treated this way for months often need weeks of tablets to clear. Stop any such cream, take the tube to your appointment, and let your doctor see what has been used.
How long do fungal nails take to clear?
Longer than anything else in dermatology. Treatment usually runs three to six months for fingernails and nine to twelve months for toenails, and the nail cannot look better until the healthy part has grown out, so there is very little to see for the first few months. Your doctor will normally confirm the diagnosis from a nail clipping first, since thickened nails also result from injury and psoriasis, and a long course of tablets should not be started on appearance alone. Blood tests are sometimes checked during treatment.
Other dermatology & cosmetology treatments
Treatment of acne and acne-related marks based on skin type, severity and recurrence
Day CareEvaluation and treatment of uneven skin tone, dark spots and other pigmentation concerns
Day CareTalk to a care coordinator about fungal skin infection
Leave a number and a care coordinator calls you back with what the treatment involves and which hospital it would be at. They book a consult only if you want one