Pharmacotherapy for onychomycosis: new and emerging treatments

Lam

et al. 2020

IAD

Background : Onychomycosis is a common fungal infection of the nail. Objective: The study aimed to provide an update on the evaluation, diagnosis, and treatment of onychomycosis. Methods: A PubMed search was completed in Clinical Queries using the key term “onychomycosis”. The search was conducted in May 2019. The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews published within the past 20 years. The search was restricted to English literature. Patents were searched using the key term “onychomycosis” in www.freepatentsonline.com. Results : Onychomycosis is a fungal infection of the nail unit. Approximately 90% of toenail and 75% of fingernail onychomycosis are caused by dermatophytes, notably Trichophyton mentagrophytes and Trichophyton rubrum. Clinical manifestations include discoloration of the nail, subungual hyperkeratosis, onycholysis, and onychauxis. The diagnosis can be confirmed by direct microscopic examination with a potassium hydroxide wet-mount preparation, histopathologic examination of the trimmed affected nail plate with a periodic-acid-Schiff stain, fungal culture, or polymerase chain reaction assays. Laboratory confirmation of onychomycosis before beginning a treatment regimen should be considered. Currently, oral terbinafine is the treatment of choice, followed by oral itraconazole. In general, topical monotherapy can be considered for mild to moderate onychomycosis and is a therapeutic option when oral antifungal agents are contraindicated or cannot be tolerated. Recent patents related to the management of onychomycosis are also discussed. Conclusion: Oral antifungal therapies are effective, but significant adverse effects limit their use. Although topical antifungal therapies have minimal adverse events, they are less effective than oral antifungal therapies, due to poor nail penetration. Therefore, there is a need for exploring more effective and/or alternative treatment modalities for the treatment of onychomycosis which are safer and more effective.

Section: Treatmentmentioning

confidence: 99%

“…Oral antifungal therapy is considered the gold standard for onychomycosis both in children and adults because of shorter courses of treatment and higher cure rates when compared with topical antifungal therapy [ 88 , 95 , 97 , 98 ]. The incidence of adverse events associated with oral antifungal agents is lower in children [ 6 ].…”

Section: Treatmentmentioning

confidence: 99%

Onychomycosis: An Updated Review

Lam

et al. 2020

IAD

J of Cosmetic Dermatology

“…It is an important problem, as it may cause local pain, paresthesia, difficulties in performing activities of daily life, and impair social interactions . Trauma, older age, diabetes, peripheral vascular disease, immunosuppression, tinea pedis, psoriasis, and family history of onychomycosis are risk factors for developing this fungal infection …”

Section: Introductionmentioning

confidence: 99%

Effect of monoterpenes on ex vivo transungual delivery of itraconazole for the management of onychomycosis

Abdollahi

Jafariazar

Afshar

2020

Background Onychomycosis, a fungal nail infection, is an important problem as it may cause local pain, paresthesia, difficulties in performing activities of daily life, and impair social interactions. Systemic treatment of onychomycosis presents safety issues due to possible drug‐drug interactions and severe side effects. Although topical therapy of onychomycosis is advantageous due to its localized effect, the efficacy of such therapy depends on achieving effective concentrations of antifungal agents at the infection site. An approach to reach to this end would be driving benefit from synergic activity of antifungal agents for example itraconazole and monoterpenes. However, because of low transungual penetration of itraconazole, a molecule with high molecular weight and very low water‐solubility, the effect of the latter compounds on itraconazole nail delivery should be investigated, which was the aim of this study. Methods Ex vivo permeation experiments were carried out through soaking the nail clippings of ten healthy volunteers in control and working solutions containing itraconazole (1 mg mL−1) and itraconazole (1 mg mL−1) plus 6% of each monoterpene including camphor, eucalyptol, menthol, and thymol, respectively, for 36 hours. The amount of itraconazole in nail clippings was quantified hereafter using a validated HPLC method. Results Statistical analysis showed that itraconazole transungual permeation was not influenced by the studied monoterpenes (P value > .05). Conclusion These results provided a new perspective for designing topical dosage forms for the treatment of onychomycosis.

“…Treatment options for onychomycosis include oral antifungal therapies, topical antifungal therapies, surgical removal of the nail plate, debridement, and device‐based treatments. The use of topical agents should be limited to cases involving less than half of the distal nail plate or for patients unable to tolerate systemic treatment 12 . Topical treatment includes ciclopirox 8% nail lacquer, amorolfine, tioconazole 28% solution, efinaconazole 10% solution, and tavaborole 5% solution 2 .…”

Section: Introductionmentioning

confidence: 99%

In vitro antifungal susceptibility testing of fungi in patients with onychomycosis

El‐Hamd

Elhameed

Shalaby

et al. 2020

Dermatologic Therapy

Onychomycosis is the most common nail disorder. To examine in vitro antifungal susceptibility of fungi among onychomycosis patients. The study included 68 patients with onychomycosis. Nail specimens were cultured on Sabouraud dextrose agar and Dermasel agar base‐media. Isolated fungi were subjected to antifungal susceptibility tests against terbinafine, itraconazole, fluconazole, and griseofulvin. Candida species (Candida spp.) were detected in 32.4% of the cases of candidal onychomycosis (n = 37), 23.5% of the cases of distal and lateral subungual onychomycosis (n = 17), and 21.4% of the cases of total dystrophic onychomycosis (n = 14). Candida spp. were sensitive to fluconazole in 73.5%, itraconazole in 58.8%, and terbinafine in 5.9% of the cases. Aspergillus spp. were sensitive to itraconazole in all cases, and terbinafine in 87.5% of cases. Penicillium spp. were sensitive to itraconazole and terbinafine in 88.9% and 77.8% of cases, respectively. Trichophyton spp. were sensitive to terbinafine and resistant to itraconazole. Microsporum spp. were sensitive to itraconazole and resistance to terbinafine. All isolated fungi were resistant to griseofulvin. An increasing proportion of Candida spp. was observed among patients with different clinical varieties of onychomycosis. Candida spp. were highly sensitive to fluconazole and a lesser extent to itraconazole.