A novel aqueous metronidazole 1% gel with hydrosolubilizing agents (HSA-3).

Rosacea is a common chronic dermatosis that often is characterized by the presence of facial erythema, visible blood vessels, papules, and pustules. Because the face is the predominant site of involvement, rosacea may cause serious psychologic trauma and can significantly affect the quality of life of individuals with the condition. The first topical therapy approved for rosacea by the US Food and Drug Administration was metronidazole for the treatment of inflammatory lesions and erythema. A stable aqueous gel formulation of 1% metronidazole has been developed with the novel combination of hydrosolubilizing agents. Metronidazole 1% gel is a clear gel that exhibits advantageous qualities. Some features of the new product include being highly spreadable, easy to use, cosmetically friendly, ultramild, nondrying, and moisturizing. Data are presented from a 21-day cumulative irritation study, an assessment of skin barrier function, an in vitro skin penetration study, an absorption following maximal topical exposure study, and a skin hydration study.