As a result, the concentration of an applied drug can drop ~1000-fold across the width of the nail and fail to reach the minimum inhibitory concentration (MIC) needed to arrest fungal growth. When a drug is applied topically, it can accumulate in the dorsal nail surface layer and display very limited diffusion into the deep ventral layer and the bed. The upper (dorsal) layer constitutes the main barrier to drug diffusion through the nail plate despite having a thickness of only a few cell layers. The ventral nail plate and the subungual keratin in the nail bed are the layers that are most likely to be infected by fungi, such as Trichophyton rubrum and T. The nail plate is composed of three layers: the dorsal–superficial, intermediate, and ventral layers. The efficacy of topically applied antifungal agents is hampered by the need for the agent to pass through the human nail. Both systemic and topical antifungal agents are used as treatments for onychomycosis. It most commonly affects the nails of the hallux and is more prevalent in men than women, which is possibly because the male hallux nail is generally thicker than the female nail (1.68 mm versus 1.38 mm). Onychomycosis is a fungal infection of toenails and fingernails.

Calibre 50 vallejo