Cosmetic agents for simultaneously lightening and temporarily shaping keratin fibers include a specific thickener and also at least one oxidant and have a viscosity of from 31,000 to 90,000 mPas. Despite the high viscosity, the agents can be easily removed from the packaging and moreover can be homogeneously applied to the keratin fibers without said agents dripping after application. The agents result in a homogeneous lightening and a good hairstyle hold. A method for lightening and temporarily shaping keratin fibers uses such cosmetic agents.
