Medicated patch comprising a support and a pressure sensitive adhesive layer provided on the support and having an acid number of no more than 28, in which the pressure sensitive adhesive layer comprises a composition containing, such as medicinal agent, varenicline in its free base form, a metal salt, an adhesive base material and an adsorbent that adsorbs a polar solvent in the composition, in which varenicline in its free base form and the salt of metal by a neutralization reaction between an addition salt of varenicline acid and an alkali metal hydroxide, which is added in an amount to convert all or a portion of the varenicline into the free base form, in which the salt of Acid addition of medicinal agent is selected from hydrochloride, acetic acid salt, sulfuric acid salt, maleic acid salt, oxalic acid salt, citric acid salt, iodhydric acid salt, hydrobromic acid salt, salt of mesilic acid, salt of tartaric acid or salt of succinic acid of the medicinal agent, in which the composition has a pH of 7.5 or greater, the pH being the pH of an aqueous solution obtained by mixing the medicated patch in water for dissolve the water soluble components, and in which the adhesive base material is an acrylic based polymer that does not contain carboxyl groups.Parche medicado que comprende un soporte y una capa de adhesivo sensible a la presion proporcionada sobre el soporte y que tiene un indice de acidez de no mas de 28, en el que la capa de adhesivo sensible a la presion comprende una composicion que contiene, como agente medicinal, vareniclina en su forma de base libre, una sal de metal, un material de base de adhesivo y un adsorbente que adsorbe un disolvente polar en la composicion, en el que pueden obtenerse vareniclina en su forma de base libre y la sal de metal mediante una reaccion de neutralizacion entre una sal de adicion de acido de vareniclina y un hidroxido de metal alcalino, que se anade en una cantidad para convertir toda o una porcion de la vareniclina en
