Systemic treatments

Currently, systemic treatment is the most effective method of curing onychomycosis. Even so, between 20-25% of patients fail to respond [11]. Terbina-fine (1) and itraconazole (2) are the two systemic treatments of choice with ter-binafine showing greater efficacy than itraconazole and lower rates of recurrence

Terbinafine (1), a representative of the allylamine class of antifungal agents, inhibits squalene epoxidase [16,17] and thereby prevents the biosynthesis of ergos-terol, a key ingredient in the fungal cell wall. Terbinafine is active against dermatophytes, M. furfur, Aspergillus species and some Candida species including C. parapsilosis; however, it is fungistatic against C. albicans [2]. A single oral dose of 250 mg terbinafine given to humans produces peak plasma concentrations of 1 mg| mL within two hours [14]. It is > 99% protein bound and has a half-life of about 36 hours. It is administered at a dose of 250mg once daily for 6 weeks for finger nails or 12 weeks for toe nails [14]. One study showed that terbinafine localizes in the stratum corneum via sebum [18]. Terbinafine has a cLogP of 6.5 and a molecular weigh of 292 Da.

Itraconazole (2), which is from the azole class of antifungal agents, inhibits la-nosterol 14 a-demethylase and thus stops the biosynthesis of ergosterol. It has broad spectrum activity against species including dermatophytes, Candida species, Aspergillus species and M. furfur [2]. Blood levels of itraconazole after a single 200mg dose given to humans reached a peak level of 0.2-0.3 mg/mL after 4-5 hours [15]. It is 99.8% protein bound and has a half-life of 21 hours. It is administered either 200 mg once daily for 12 weeks or 200 mg twice daily for 7 days followed by 3 weeks with no treatment and repeated for three months. Like terbinafine,

itraconazole also localizes in the stratum corneum via sebum but at much lower levels [18,19]. Itraconazole has a cLogP of 3.3 and molecular weight of 706 Da.

Griseofulvin (3), isolated from Pénicillium griseofulvin in 1939 [20], has a limited spectrum of activity. It is fungistatic against dermatophytes only and works by binding to microtubular proteins thus inhibiting cell mitosis. It has a cLogP of 2.2 and a molecular weight of 353 Da.

The commonly used antifungal agent, fluconazole, has also been prescribed, offlabel, for the treatment of onychomycosis.

Natural Remedy For Yeast Infections

Natural Remedy For Yeast Infections

If you have ever had to put up with the misery of having a yeast infection, you will undoubtedly know just how much of a ‘bummer’ it is.

Get My Free Ebook

Post a comment