When patients present with onychomycosis, their main concern is virtually always about the appearance of the nail. In early distal lateral sub-ungual onychomycosis its usually the colour change that most sufferers find disturbing. Following diagnosis, traditionally the treatment of choice for mild nail infection is topical treatment with an antifungal. Amorolfine 5% lacquer is the drug suggested by the British Association of Dermatologists guidelines for onychomycosis.
As podiatrists, we will reduce the nail, issue the lacquer to the patient and tell them to apply it weekly to the affected nails. The next question that usually arises is “Can I still use nail varnish with this?” as the patient, quite understandably, wants to mask the visually unappealing fungal nail infection and still have good looking toenails even during treatment.
I was always taught that nail varnish and antifungal nail lacque are uneasy bedfellows on the premise that the varnish would somehow inhibit or negate the good effects of the prescribed drug. However, I was interested to read a study which set out to investigate that very idea – does the application of nail varnish have any effect on the outcome of patients using amorolfine?
This study was led by one of the world’s authorities on onychomycosis, Dr Bardur Sigurgeirsson. A respected dermatologist with over 100 publications in his field. [Iceland, incidentally, has a lot of onychomycosis hence the large amount of fungal foot infection research emanating from the country]. Back to the topic though. The research team recruited 50 subjects with mycologically confirmed onychomycosis and allocated them randomly into two groups – those using amorolfine weekly and those using amorolfine BUT applying a (Loreal) nail varnish 24 hours later over the top. At the conclusion, they discovered that both groups had similar outcomes in terms of cure rates and that when nail samples from all patients were tested for antifungal drug content they were equally effective at inhibiting the usual dermatophytes in the laboratory, suggesting that drug penetration had been good.
So ultimately when using amorolfine do tell patients it’s perfectly acceptable to use varnish provided its applied 24 hours after the amorolfine. Also, that prior to re-applying the antifungal lacquer the nail should be thoroughly cleaned and be free of varnish prior to the next application.
Paper: Sigurgeirsson, B., M. A. Ghannoum, H. Osman-Ponchet, N. Kerrouche and F. Sidou (2016). "Application of cosmetic nail varnish does not affect the antifungal efficacy of amorolfine 5% nail lacquer in the treatment of distal subungual toenail onychomycosis: results of a randomised active-controlled study and in vitro assays." Mycoses 59(5): 319-326.