A method for preparing a product for treating the skin and mucous membranes comprises the steps of making available a suitable quantity of trichloracetic acid, making available a suitable quantity of hydrogen peroxide, making a first mixture of the trichloracetic acid and the hydrogen peroxide, making available a determinate quantity of the basic compound able to achieve a buffer effect of the trichloracetic acid comprised in the first mixture, and adding the basic compound to the first mixture in order to buffer the first mixture comprising the trichloracetic acid.
