Fungal Toenails- What are your oral options?

Fungal toenail infections, or onychomycosis, are a prevalent condition affecting many individuals of varying ages. These infections can cause nails to thicken, discolour and become brittle, often leading to discomfort and self-consciousness. While topical and light therapy treatments exist, oral medications are usually more effective, especially for severe or resistant cases. The emergence of resistant strains of toenail fungus, particularly following the COVID-19 pandemic, poses a significant challenge.

Oral anti-fungal options for the treatment of onychomycosis

 Terbinafine

Terbinafine, known by the brand name Lamisil, is one of the most frequently prescribed oral antifungal medications for toenail fungus. Indicated primarily for onychomycosis caused by dermatophytes, terbinafine works by inhibiting the synthesis of ergosterol, an essential component of fungal cell membranes. The typical regimen is one tablet daily for 6 to 12 weeks, depending on the severity of the infection. 

Effectiveness: Terbinafine has traditionally boasted a high success rate, with pre-pandemic studies indicating that up to 70% of patients achieve complete cure after the treatment course.

Contraindications: Terbinafine is contraindicated during pregnancy and in patients with chronic or active liver disease. It should also be used cautiously in individuals with renal impairment.

 Side Effects: Common side effects include gastrointestinal disturbances, headache and rash. Serious but rare side effects include liver toxicity, severe skin reactions and taste disturbances.

Itraconazole

Itraconazole, sold under the brand name Sporanox, is another effective oral antifungal for treating toenail fungus. It is indicated for onychomycosis caused by dermatophytes, yeasts and moulds. Itraconazole is usually administered in pulse therapy, with the medication taken for one week per month over several months.

Effectiveness: Itraconazole has been shown to have a success rate of about 60-70%, making it a reliable treatment option with potentially fewer and less severe side effects than terbinafine.

Contraindications: Itraconazole should not be used during pregnancy and in patients with heart failure or those on certain medications that can interact, such as specific cholesterol-lowering drugs and some antiarrhythmics.

 Side Effects: Side effects may include nausea, vomiting, abdominal pain, and headache. Serious side effects can involve liver toxicity, heart failure and severe skin reactions.

Fluconazole

Fluconazole, known as Diflucan, is another treatment option for toenail fungus, though it is less commonly prescribed than terbinafine or itraconazole. It is indicated for fungal infections caused by yeasts and moulds, with a typical dosage regimen involving weekly doses for several months.

Effectiveness: Fluconazole’s success rate is lower compared to terbinafine and itraconazole, with cure rates around 50-60%.

Contraindications: Fluconazole should be avoided in pregnancy and patients with known hypersensitivity to the drug. It should be used cautiously in those with liver or kidney disease.

Side Effects: Common side effects include gastrointestinal upset, headache and dizziness. Rare side effects encompass liver toxicity, severe skin reactions and changes to cardiac rhythm.

Griseofulvin

Griseofulvin is used to treat fungal infections of the scalp, fingernails and toenails. It is was one of the first oral drugs approved for fungal toenails but is has largely been replaced by newer more effective drugs like terbinafine that work over a much shorter duration. The dosage for this drug can be 1-2 tablets daily over 12-18 months for toenail treatment.

Effectiveness: Griseofulvin’s success rate in toenails is much lower compared to other oral antifungal drugs, making it rarely used today, with success rates reported around 30%.

Contraindications: Griseofulvin should be avoided in pregnancy and patients with known hypersensitivity to the drug. It should be used cautiously in those with liver disease.

Side Effects: It most commonly causes gastrointestinal issues of nausea, vomiting, and diarrhea, as well as headaches.

The advantage of a pulsed oral antifungal regime

For some individuals the idea of oral medication, their potential side effects and repercussions on the liver, is a significant cause for concern. Pulsed oral antifungal therapy however, can be a helpful mode of dosage frequency that reduces the total dosage over the course of treatment and therefore may minimise undesirable systemic effects. More specifically, it is where medication is given in bursts, rather than continuously, offering a balance between effectiveness and reduced side effects. An example of this might be taking one tablet daily for one week per month over 12 months, as opposed to one tablet daily for the whole 3 months.

The oral antifungals Itraconazole and terbinafine particularly lend themselves well to pulsed therapy, as they stay in the hair and nails far longer than griseofulvin or fluconazole. Pulsed terbinafine and itraconazole maintains therapeutic drug levels at the target sites without subjecting patients to the sustained high blood levels experienced with daily dosage. In turn this can reduce the risk of liver toxicity, reduce potential side effects and improve patient compliance, without a reduction in effectiveness.

Resistant onychomycotic strains

 During the COVID-19 pandemic and subsequent lockdowns, individuals had a lot more time to ponder the state of their toenails or to act on long-standing stubborn fungal nail infections. As a consequence, there was an overall increase in the use of both topical and oral antifungals to treat such infections. It is thought that some fungal strains have built up resistance to conventional treatments, which in the aftermath of the global pandemic, is now complicating the management of onychomycosis.

Notably, the Southeast Asia fungal strain has shown resistance to terbinafine, with some dermatologists seeing no improvement in the health of fungal toenails despite patients taking maximum dosages of oral terbinafine, in addition to adjunct treatments such as topical antifungals and light therapies. It is believed that itraconazole however, can still effectively work against the Southeast Asia fungal strain with little evidence of resistance seen at this stage.

How our Melbourne Podiatrists help in the treatment of fungal toenails

Our Melbourne podiatrists are skilled in the diagnosis of fungal toenails and can help distinguish them from thickened damaged toenails. They can advise you on a range of antifungal toenail treatments, from topical treatments to more advanced treatments like PACT Nail Therapy. Our podiatrists will advise you on the best treatment and can periodically reduce the bulk of fungal toenails with specialised equipment, to improve long term outcomes.

For more severe fungal toenail infections our podiatrists, in conjunction with your GP, can determine if oral antifungal treatment is most appropriate treatment option, and can monitor your progress with regular podiatry debridement treatments.

Do you have fungal toenails?

At our Melbourne foot clinic our podiatrists are experts in fungal toenails and can advise you on the most effective treatment option for your case.

So if you suffer from unsightly fungal toenails, book an appointment with one of our friendly podiatrists today!