Focal Drug Delivery to the Nail

Abstract

AbstractDisease of the nail unit is fairly common and may be entirely localised to the nail or reflect deeper systemic conditions. The disorders are sometimes, but not always, benign and can sometimes cause physical pain as well as social embarrassment and depression when long term and recalcitrant to treatment. The two most common nail diseases are fungal infections and psoriasis, which are largely treated using oral antifungals and steroid injections into the nail unit, respectively. Due to the adverse effects and drug interactions of the oral antifungals and the pain of injections, topical formulations have also been used for many years, with varying (mainly limited) success rates. Interest in formulating more effective topical nail medicines has however been steadily increasing in recent years and a range of new approaches are being investigated. In this Chapter, the nail unit, its diseases and their focal therapy is discussed. Focal drug application to the nail is performed entirely for local action to treat diseases of the nail unit. The latter, although serving numerous functions, is generally taken for granted until affected by disease. Even then, the disease is frequently ignored and remains untreated (often for years), due to various reasons, such as, perceived unimportance of a ‘cosmetic problem’ and the lack of a rapid cure. While some nail diseases are fairly benign, for example, nail yellowing in smokers, others can be extremely painful and serious, for example, infections and malignant tumours. Thus, nail diseases have a significant impact on the quality of life of sufferers, for example, pain upon wearing footwear with severely diseased toenails, while disfigured fingernails can inhibit social/work interactions especially if the hands are involved in the said interactions. Successful treatment of nail diseases is therefore of critical importance.KeywordsNail PlateFocal TherapyFluocinolone AcetonideNail PsoriasisNail MatrixThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.