Antifungal medicines

What are antifungal medicines, and how do they work?

Antifungal therapy means using medicines to treat fungal infections, which most often affect the skin, hair and nails¹. Some medicines stop the fungus growing so your immune system can clear it; others kill it². Most creams for tinea (ringworm and athlete's foot) only slow the fungus, which is why you keep using them after the skin looks clear².

The right medicine depends on the type of infection and where it is. Terbinafine is commonly prescribed first for skin and nail infections³. A fungal nail infection (onychomycosis) is long-lasting and hard to clear completely⁴.

What is it used for, and how well does it work?

Antifungals are commonly used for ringworm, athlete's foot and fungal nail infections¹. The strongest backing is for toenail infection in adults. Antifungal tablets clear it much more often than a dummy treatment⁵, and terbinafine is described as the treatment of choice⁶. Nail paints and solutions also work better than a dummy treatment, but they rarely clear the nail completely, so expect partial improvement⁷.

For children, small studies suggest tablets can clear nail infections, but there are only a few of them⁸. Your result depends on your age and general health, the type of fungus, and how many nails and how much of each nail are affected⁶.

Are antifungal medicines right for me?

Often, yes, but the choice depends on your age, general health, the type of fungus and how many nails are affected⁶. Tablets are more likely to clear a nail infection than creams or paints, but they carry more risks and need closer checking⁶.

Tablets may not be suitable if you have liver or kidney disease, or if you're pregnant or breastfeeding⁹. If you're pregnant or breastfeeding, speak to a doctor or pharmacist before using any antifungal¹. Azole tablets can interact with many other medicines, including blood thinners and immune-suppressing medicines, so tell your prescriber about everything you take¹⁰. Children can use some antifungals, but doses are set by age, so ask a pharmacist or GP¹.

What does treatment involve?

It's a course of medicine rather than a set of sessions. A pharmacist or GP can advise which product suits you¹, and the prescriber tells you how long to take it. Before tablets are considered, a lab test can confirm the nail infection is fungal⁶.

• Creams for tinea: usually 1–2 weeks, then 2 more weeks after the signs have gone².
• Nail paints and solutions: brushed onto the nail and typically used for 6–12 months. Improvement can take several months⁹, so try not to give up early.
• Terbinafine tablets for nails: may be taken for up to 3 months, sometimes longer. If it isn't working, your doctor may extend the course or change the medicine¹¹.

A liver blood test is recommended before oral terbinafine, and again 4–6 weeks after starting¹².

What are the risks and side effects?

Side effects of antifungals are usually mild and don't last long¹. Creams and paints mostly cause skin reactions where they're applied, and some nail solutions seem more likely to⁷.

Tablets carry more risk. Terbinafine can rarely affect the liver¹¹¹², and severe changes can come on quickly enough to be missed by a routine blood test¹³, so it helps to know the warning signs below. Fluconazole or itraconazole taken with alcohol can raise the risk of liver injury¹⁴.

How does it compare with other options?

For toenail infection in adults, tablets taken continuously did better than nail paints and solutions¹⁵. The trade-off: tablets are more likely to clear the nail but bring more risks and need closer monitoring, while paints and solutions are gentler but less likely to clear the nail completely⁶⁷. A pharmacist or GP can talk through which suits you.

Laser and other device treatments aren't a proven alternative: it isn't clear yet whether they work⁷¹⁵. The same goes for combining treatments¹⁵.