The darkening of buttocks after sitting for a long time is considered to be caused by physiological factors such as buttock pressure, friction and pigmentation, which can be improved through general treatment, medication and physical therapy. 1. General treatment: For people whose buttocks are darkened after sitting for a long time, they need to improve their living habits and avoid friction and stimulation of the buttocks or sitting for a long time to prevent the symptoms from aggravating. 2. medication: it is recommended that people with darkened buttocks after sitting for a long time use hydroquinone, deoxy arbutin and tretinoin as prescribed by the doctor, which can inhibit the activity of tyrosinase and thus eliminate melanin deposits. Adapalene gel, retinoic acid cream and other retinoic acid drugs can promote epidermal renewal, help reduce hyperpigmentation. 3. Physical therapy: laser treatment is one of the effective means to improve melanin pigmentation, based on the principle of selective photothermal effect on the local skin, can promote the synthesis of fibroblasts, secretion of collagen fibers, so as to achieve the effect of removing pigmentation, rejuvenation and so on. If the buttocks sit for a long time black situation, daily need to develop good habits, avoid sitting for a long time. If you need to take drugs, physical therapy and other ways to deal with, it is recommended to go to a regular hospital, with the doctor for standardized treatment, do not blindly deal with their own.