Thursday, August 2, 2018

Toenail Fungus: Wow, that's a lot on your plate

The issue?

Toenail fungus is not the most fun topic, but it is something we must talk about, especially when nail infections  currently effects 6.4% of Canadians.1 This is approximately 2.3 million cases of nail fungus in Canada, most of which are toenail infections. Toenail fungus is usually preceded by athlete's foot, but it can occur independently. Toenail infections can cause several complications and should be treated promptly. A common issue with toenail infections is the aftermath after a successful treatment.

There are two terms used to define a successful treatment for toenail fungal infections. A mycological cure refers to the eradication of the fungi at the nail. A complete cure is defined by the eradication of fungi at the nail and the appearance of a healthy-looking nail. Most successful treatments of toenail fungus end with mycological cure, leaving patients with discolored and thickened nails. 

The hard part?

Unfortunately, the medications available for treating toenail fungus are not great at achieving complete cures. Topical antifungals and oral antifungals are the preferred therapy for treating toenail infections.

Efinaconazole and Ciclopirox are the two available topical therapies for the treatment of toenail fungus and have a respective 17% and 8.5 % complete cure rate.2 Achieving these cure rates are difficult because it requires patient's to be compliant with once daily usage for 48 weeks. 

The oral therapies Itraconazole and Terbinafine have the advantage of a lower duration of therapy (12 weeks) but come with unwanted drug interactions. Oral antifungals are notorious for their plethora of drug interactions, which can effect people taking medications for:
  • Depression
  • Pain
  • Migraines
  • Blood Pressure
  • Heart rate
  • Cholesterol
  • Psychosis
  • Anxiety
  • Sleep Deprivation
  • Urinary Incontinence
  • Heart Burn

Since several drug interactions exist it is difficult to treat most patients without risk of interactions. All this extra risk coincides with a higher cure rate, but not much. Terbinafine has the highest complete cure rate for oral antifungals commonly used. When used optimally, it’s complete cure rate is 38%.2

Good hygiene:

Low complete cure rates are a reason for concern for fungal toenail infections. Good hygiene practices can decrease the risk of contracting a fungal infection.

Hygiene Practices:
  • Wearing shoes that minimize humidity. Preferable shoes made of canvas or leather.
  • Avoid sharing toe nail clippers, towels, and other foot care devices with individuals
  • Keep nails clean and short
  • Avoid being bare footed in publicly shared spaces such as swimming pools, nail salons, gym locker rooms.
  • Dry feet immediately after washing
  • Wash feet with soap and water every day
  • Change socks worn each day, and even more frequently for physically activity individuals or those with a propensity to sweat
  • Wear socks preferably made of acrylic, cotton, polypropylene or wool.

Quick Tip: All these hygiene practices are valid for preventing both nail and foot fungal infections.

Although the mycological cure rate is respectable for most antifungals, the complete cure rate is usually low. Hopefully this will keep you on your toes, and get you to make the appropriate changes to your daily routine to decrease your risk.

Thank you for your time, and have a nice long weekend!

Derick Oduro 

1) Gupta AK, Gupta G, Jain HC et al. The prevalence of unsuspected onychomycosis and its causative organisms in a multicentre Canadian sample of 30,000 patients visiting physicians' offices. J Eur Acad Dermatol Venereol 2016;30(9):1567-72.

2) Gupta AK et al. J Cutan Med Surg. 2015 Sep-Oct;19(5):440-9. doi: 10.1177/1203475415581310. Epub 2015 Apr