Should You Use Oral Drugs For Onychomycosis?
- Volume 15 - Issue 1 - January 2002
- 6427 reads
- 0 comments
Patients with onychomycosis are becoming increasingly aware that oral antifungals have the potential to cure their underlying infections, yet a recent study finds the majority of podiatrists continue to rely largely on debridement to provide symptomatic relief. As a profession, we’re quite knowledgeable about the various approaches to treating onychomycosis, but this study reveals that current treatment practices are aligned only partially with patients’ attitudes and behaviors regarding their infections. The study, a survey of over 900 onychomycosis patients and over 600 doctors conducted by the research firm Lieberman Research Associates, suggests that in addition to providing the symptomatic relief our patients desire, we should start treating onychomycosis as we would any other infection — medically.
A Review Of Treatments For Onychomycosis
The therapeutic approaches to managing onychomycosis range from palliative to curative and include nail debridement, topical therapy, oral antifungals or some combination of these treatments.1 For DPMs, debridement and topical medications have long been the most popular forms of treating onychomycosis.1,2
When you debride, you can effectively relieve the patient’s pain, help prevent subungual ulceration, reduce the fungal load and improve the appearance of the nail.2 While debriding mycotic nails does not cure the underlying infection, it does help address a patient’s desire for symptomatic relief, plays a role in managing the infection and helps avoid serious morbidity.1,3
Topical preparations for nail infections also are generally regarded as palliative therapy due mainly to their questionable efficacy. The low cure rates probably result from the inability of these agents to penetrate the nail plate keratin and contact the target tissue in sufficient quantity and duration to kill the invading fungi effectively.1
I should note that one topical treatment for onychomycosis, 8 percent ciclopirox topical solution, reportedly is more effective than older topical agents. Double-blind, placebo-controlled clinical trials found that once-a-day application of this FDA-approved modality for 48 straight weeks caused mycological cure rates ranging between 29 percent and 36 percent and complete cure rates (no nail involvement and negative mycology) between 5.5 percent and 8.5 percent.4
In general, you’ll find topical therapies show their most beneficial effects when your patient has a small degree of clinical involvement.3 Using topical preparations can help you treat onychomycosis as they can soften the nail plate and help contain the infection. However, be aware the long treatment courses frequently required often result in poor patient compliance.1,2
Griseofulvin and ketoconazole, the older-generation oral antifungal agents that have been used to treat onychomycosis, suffer from low efficacy and high relapse rates.2,5 Pharmacodynamic characteristics of both of these agents require that you administer these drugs in prolonged treatment regimens lasting up to 18 months for toenail onychomycosis.1,2 The long-term dosing regimens, potential for adverse experiences, poor efficacy and frequent recurrences have caused many physicians to avoid prescribing griseofulvin and ketoconazole for onychomycosis.
What You Should Know
About Itraconazole And Terbinafine
Within the last six years, the FDA has approved two newer oral antifungal agents (itraconazole and terbinafine) for treating onychomycosis. These current-generation oral antifungal agents offer a favorable safety profile, shorter courses of treatment, lower relapse rates and superior efficacy compared to griseofulvin and ketoconazole.
Based on pivotal trials, itraconazole boasts a mycological cure rate of 54 percent (complete cure rate of 14 percent), while terbinafine has a 70 percent mycological cure rate (complete cure rate of 38 percent).6,7 Unlike the older-generation oral antifungals, itraconazole and terbinafine rapidly enter the nail bed and diffuse into the entire nail plate where they accumulate. Given this “reservoir effect,” which allows these agents to remain active long after you’ve ceased providing treatment, you can give patients shorter courses of therapy.2,5