uniton 4 cream for treating deep pigmentation in the skin. uniton 4 cream contains ingredients that help nourish the skin and treat deep pigmentation to lighten dark skin areas. Therefore, it is used in the treatment of hyperpigmentation, melasma, and freckles. It works by inhibiting melanin production processes in the cells. It contains glycolic acid, kojic acid, and ascorbyl tetraisopalmitate, or what is known as vitamin C.