Galenic and dermopharmaceutical effectiveness study of an emulsified pharmaceutical form with retinoic acid.

Retinoic acid constitutes an active that is already being used extensively in the fight against cutaneous aging. After a period in which certain scientific publications questioned its use, today there is no doubt that retinoic acid continues to be an active with wide possibilities of use when it is formulated and administered correctly. In this work we propose a new formulation that, on the basis of a modern self-emulsifying excipient, incorporates retinoic acid in its composition. The work protocol is structured in the following points of study. Rheological assay: Shear rate, shear stress, viscosity, thixotropy, rheodestruction, and extensibility measurements were carried out. Other pharmacotechnical assays: External appearance, interposition type, and pH control were studied. Dermopharmaceutical effectiveness study: Biophysical non-invasive techniques were applied, according to a standardized work method. The following considerations can be made from the results: the layout of the rheograms could fit, in principle, inside a non-Newtonian-shear-thinning flow behavior, with similar rheodestruction profiles. The hysteresis values, as well as the extensibility indexes that were obtained, determined a good degree of applicability. From the whole of results, we could conclude that the formulation proposed is profiled like an emulsified pharmaceutical form with an excellent cosmetological adaptation, eudermic pH, and soft emollient action, which prohibits the loss of superficial water that maintains the retinoic acid action.