Athlete’s foot can become “untreatable” even with the strongest over-the-counter creams due to the emergence of drug-resistant strains of the bacteria that causes the common skin infection.
One of the most commonly used drugs, Lamisil Once, was able to fight the condition with a single dose when it hit the market in the 1990s — but more and more patients are finding the remedy useless, experts say.
And concerns aren’t just about athlete’s foot, which causes the skin between the toes to become sore and cracked. One doctor said antifungal treatments are now ineffective in about a third of all skin infections he treats.
Athlete’s foot is caused by a type of fungus called dermatophyte, which also causes ringworm — characterized by a painful, scaly, red rash that can appear anywhere on the body. These infections affect millions of people in the UK every year.
Much has been written about bacterial infections being resistant to antibiotics, making once treatable conditions such as urinary tract infections potentially deadly.
Athlete’s foot may become ‘untreatable’ even with the strongest over-the-counter creams due to the emergence of drug-resistant strains of the bacteria that causes the common skin infection
But experts see a similar pattern with everyday yeast infections. And there are fears that the NHS will soon run out of effective treatments.
‘We are seeing more and more drug-resistant fungal infections of the skin and quite frankly the problem has not received nearly enough attention,’ says Dr Neil Stone, infectious disease and microbiology adviser at University College London Hospitals NHS Foundation Trust.
“These kinds of problems are very common and if the treatments we rely on stop working, it will be a huge health problem with huge consequences.”
About 15 percent of people have had a fungal skin infection in the past year. The scaly, red rash is much more common in older people, affecting about half of those over the age of 70.
The drug recommended by the NHS to treat athlete’s foot is terbinafine, the active ingredient found in Lamisil Once and other over-the-counter treatments. But this is one of the drugs that is becoming less and less effective, experts warn
There are several strains of dermatophytes, most of which are transmitted through skin-to-skin contact. The fungal spores can live on the skin and under fingernails for some time without causing a rash, and they thrive in warm, moist places such as wet towels and the floors of locker rooms.
This is why athlete’s foot—a form of dermatophyte that gets between the toes—is often picked up in communal showers.
The fungi can also infect the scalp, causing a form of dandruff.
Drying the affected area — using talcum powder, for example — may help lessen the severity of the rash, but it won’t cure it. Specific antifungal treatments are the only effective way to destroy dermatophytes.
The drug recommended by the NHS is terbinafine, the active ingredient found in Lamisil Once and other over-the-counter treatments. But this is one of the drugs that is becoming less and less effective, experts warn.
“This problem has been bubbling up over the past five years and now we’ve reached a point where these hard-to-treat infections are becoming commonplace,” said Professor Darius Armstrong-James, an infectious disease expert at Imperial College London. ‘Patients often have to use multiple applications of terbinafine. That is the case in about a third of the cases.’
Drug-resistant infections may respond to stronger prescription antifungal drugs or combinations of these drugs used simultaneously and for long periods of time. However, these treatments sometimes cause unpleasant side effects, including intestinal problems and nausea.
Prof Armstrong-James classifies a ‘significant’ number of his patients as ‘untreatable’ – meaning they have to take antifungal drugs almost continuously to control their infections.
Like bacteria, fungi, a category of organisms that includes yeast and mushrooms, can evolve to develop stronger defenses against drugs designed to kill them. And overuse of antifungal medications can accelerate the development of difficult-to-treat strains.
Experts point to the frequent use of fungicidal pesticides in the food industry, which protect fruits and vegetables from spoilage due to fungal infections.
‘This creates the perfect conditions for the formation of resistant strains of fungi,’ says Prof. Armstrong-James.
‘They then end up in animals and people.’
The overuse of antifungal medications is also the source of the problem.
“Patients keep going back to the pharmacy to get more terbinafine, even if it doesn’t work, or they stop treatment before the course is finished,” says Dr Neil McCarthy, an expert on yeast infections at Queen Mary University. or London. ‘This allows the fungus to build up resistance.’
Experts say one possible solution is to make sure all antifungal treatments are prescribed by a doctor.
“A doctor can take a sample of the infection and test it in a lab to see if it’s already resistant to terbinafine before offering treatment,” says Dr McCarthy.
In 2014, European Commission scientific advisers suggested removing antifungal treatments from cosmetic products, such as dandruff shampoo, to slow the growth of drug-resistant fungi, but this has not yet happened.
Ultimately, experts say the key is to develop new drugs.
“There are only a small number of new treatments for athlete’s foot,” says Prof. Armstrong-James. “If we don’t quickly focus more research into this area, we will soon find ourselves in a position where millions of Britons are experiencing very uncomfortable, debilitating and recurrent skin infections.”