Anti-Fungal Therapy
Topical Therapy for Nail Infections
Yeast and bacterial infections of the nails are usually the result of microscopic damage to the nail plates. The nails will have either a white, thin discoloration at the tip of the nail that starts to extend toward the cuticle, or may have a greenish-black color to the nail. A mixture of 4% thymol in alcohol used twice daily until the affected area has grown out is excellent for this condition. Thymol is an antibacterial and antifungal, and alcohol also reduces moisture in skin folds and cuticles.
For treatment of onychomycosis, penetration of the topical antifungal agent through the nail plate from the surface of the nail and diffusion of the systemic antifungal drug through the nail bed may increase the total amount of antifungal activity at the site of infection. Results from an initial study in patients with onychomycosis suggest that this approach can enhance the overall efficacy of therapy. Using a combination of antifungal drugs in this manner may potentially reduce the duration of therapy and allow a reduction in dose of the oral agent, which may reduce systemic adverse effects. Physicians may also consider combining topical antifungal therapy with topical urea. Urea degrades protein, including keratin — a major component of the nail plate. Potentially, urea can soften the nail plate, making it more porous and penetrable to topical antifungal drugs. Urea ointment (40 to 55%) can be applied to the nail twice daily for two weeks. Then, topical formulations such as clotrimazole 2% and ibuprofen 2% in DMSO USP (“apply to affected nails BID for 6 weeks”) or butenafine 2% and tea tree oil 5% cream can be applied to the affected nail.
A randomized, double-blind, placebo-controlled study examined the clinical efficacy and tolerability of 2% butenafine hydrochloride and 5% Melaleuca alternifolia (tea tree) oil incorporated into a cream base to manage toenail onychomycosis. Sixty outpatients (39 M, 21 F) aged 18-80 years (mean 29.6) with 6 to 36 months duration of disease were randomized to two groups (40 active therapy and 20 placebo). After 16 weeks, 80% of patients using medicated cream were cured, as opposed to none in the placebo group. Four patients in the active treatment group experienced subjective mild inflammation without discontinuing treatment. During follow-up, no relapse occurred in cured patients and no improvement was seen in medication-resistant and placebo participants.
Audrey Kunin, M.D. http://www.dermadoctor.com/article_Nail-Fungus_57.html (accessed January 2012)
http://www.medscape.com/viewarticle/452687_8 (accessed January 2012)
Timothy J. Scott, DPM, FACFAS, Clarion, PA
Trop Med Int Health. 1999 Apr;4(4):284-7.
Treatment of toenail onychomycosis with 2% butenafine and 5% Melaleuca alternifolia (tea tree) oil in cream.
Click here to access the PubMed abstract of this article.
A recent large prospective study has shown that onychomycosis is among the most significant predictors of foot ulcer. If left untreated, toenails can become thick, causing pressure and irritation, and thus act as a trigger for more severe complications. In the treatment of onychomycosis, compliance and drug interactions are important considerations, as diabetic patients frequently take concomitant medications.
Am J Clin Dermatol. 2009;10(4):211-20.
Toenail onychomycosis in diabetic patients: issues and management.
Mayser P, Freund V, Budihardja D.
Click here to access the PubMed abstract of this article.
Study participants were treated with a solution of 1% fluconazole and 20% urea in a mixture of ethanol and water, applied once daily at bedtime. The response to this local therapy was appreciable.
J Dermatolog Treat. 2005 Feb;16(1):52-5.
Combination of fluconazole and urea in a nail lacquer for treating onychomycosis.
Baran R, Coquard F.
Click here to access the PubMed abstract of this article.
Studies have shown that antifungal agents can be of benefit in treating onychomycosis in patient populations that include the elderly, children, and immunocompromised individuals (e.g., transplant patients, Down’s patients, HIV patients, and diabetics). The treatment modality in special patient populations should take into account the clinical presentation of onychomycosis, causative organism, patient and physician preference, concomitant medications that the patient is taking, and the potential for adverse events associated with antifungal therapy.
J Cutan Med Surg. 2004 Jan-Feb;8(1):25-30. Epub 2004 Jan 23.
Treatment of onychomycosis: pros and cons of antifungal agents.
Gupta AK, Ryder JE, Skinner AR.
Click here to access the PubMed abstract of this article.
Chemical nail destruction with a combination of urea and bifonazole, followed by treatment with an antifungal ointment, can be used when the nail is markedly thickened. Non-comparative trials have shown cure rates close to 70% at three months when the matrix is not involved, and 40% with matrix involvement.
Prescrire Int. 2009 Feb;18(99):26-30.
Fungal nail infections: diagnosis and management.
Click here to access the PubMed abstract of this article.
Fungal infections of the feet are commonly associated with dry, cracked skin surrounding the plantar surface and heel fissures. Hyperkeratosis can have various etiologies, and chronic conditions are often quite difficult to treat. Moccasin tinea pedis is typically resistant to topical antifungal therapy when used as sole therapy, because the scale on the plantar surface of the foot impedes or limits the absorption of the antifungal agent. However, one study showed a 100% cure rate was achieved in 12 patients with confirmed moccasin tinea pedis who were treated with topical 40% urea cream and antifungal cream concomitantly for 2 to 3 weeks.
Cutis 2004 May;73(5):355-7
The use of 40% urea cream in the treatment of moccasin tinea pedis.
Click here to access the PubMed abstract