Introduction to fungal nails — II

By our correspondents
January 12, 2017

Who should be treated for fungal nails?

Medical treatment of onychomycosis is suggested in patients who are experiencing pain and discomfort due to the nail changes. Patients with higher risk factors for infections such as diabetes and a previous history of cellulitis (infection of the soft tissue) near the affected nails may also benefit from treatment. Poor cosmetic appearance is another reason for medical treatment.

What is the treatment for fungal nails?

Keeping nails trimmed and filed can help to reduce the amount of fungus in the nails and is highly recommended. A podiatrist or dermatologist may shave the top layer of the nail off or even remove part of the nail.

Creams and other topical medications have traditionally been less effective against nail fungus than oral medications. This is because nails are too hard for external applications to penetrate.

Prescription topical medications for fungal nails include the following:

Ciclopirox (Penlac) topical solution 8% is a medical nail lacquer that has been approved to treat finger or toenail fungus that does not involve the white portion of the nail (lunula) in people with normal immune systems. It only works about 7% of the time. The medication is applied to affected nails once daily for up to one year. The lacquer must be wiped clean with alcohol once a week. There is some evidence that using an antifungal nail lacquer containing amorolfine can prevent reinfection after a cure, with a success rate of about 70%. However, this drug is currently unavailable in the United States.

Efinaconazole (Jublia) is a medication approved in 2014. It is a topical (applied to the skin) antifungal used for the local treatment of toenail fungus due to two most common fungal species affecting nails (Trichophyton rubrum and Trichophyton mentagrophytes). Once-daily application is required for 48 weeks.

Tavaborole (Kerydin) is another new medication that is indicated for onychomycosis of the toenails. This medicine has the same indication as efinaconazole. It also requires application once daily for 48 weeks.

What is the treatment for fungal nails?

Oral antifungal therapy works about 50%-75% of the time, depending on the medication. It can take nine to 12 months to see if it has worked or not, because that is how long it takes for the nail to grow out. Even when therapy works, the fungus may come back about 20%-50% of the time.

Prescription oral medications that are effective against nail fungus include the following:

* Griseofulvin (Fulvicin, Grifulvin, Gris-Peg): This drug has been the mainstay of oral antifungal therapy for many years. Although this drug is safe, it is not very effective against toenail fungus. Disappointing long-term results have been reported. Newer agents have largely supplanted it.

* Terbinafine (Lamisil): This drug is taken daily for 12 weeks for toenails and six weeks for fingernails. The drug is safe, effective, and produces few side effects. However, it must be used with caution in patients with liver disease.

* Itraconazole (Sporanox): This is often prescribed in “pulse doses” — one week per month for two or three months. It can interact with some commonly used drugs such as the antibiotic erythromycin or certain asthma medications.

* Fluconazole (Diflucan): This drug may be given once a week for several months. The dosing of this drug may need to be modified if the patient has impaired kidney function or is taking it simultaneously with certain other medications. It is not as effective as Lamisil or Sporanox and should be used cautiously in patients with liver disease.

* A doctor will determine whether a simple blood test is needed to check for liver disease.

There are several innovative treatments that are still being tested:

* Laser therapy or photodynamic therapy uses application of light-activated agents onto the nail followed by shining light of a proper wavelength on the nail.

* Use of electrical current to help absorption of topical antifungal medications into the nail: This is also called iontophoresis.

* Use of a special nail lacquer that changes the micro-climate of the nail to make it inhospitable for the fungus to grow: If this works, it may be an inexpensive way to treat this problem in the future.

One way to definitively get rid of toenail fungus is by surgery. Surgical treatment of onychomycosis involves nail removal. However, this often only provides temporary relief, and recurrence is common unless additional antifungal medication (oral or topical) is simultaneously used. However, surgical removal may be warranted when the affected nail is associated with other factors such as trauma and or infection.

to be continued

medicinenet.com