The itchy black thighs may be caused by physical factors such as inadequate cleaning and friction, or it may be caused by medicinal rashes, chronic eczema, ringworm and other diseases, which can be improved through general treatment and medication. 1. Physiological factors: If the itching and blackness on both sides of the thighs is caused by inadequate cleaning and friction, you need to pay attention to local hygiene in your daily life, wear loose clothing and reduce local friction. 2. drug rash: itching black thighs can also be caused by drug rash, patients need to keep local clean. You can follow the doctor’s instructions to take loratadine, cetirizine and other antihistamines, to play the role of anti-itching, anti-allergy. At the same time, you can follow the doctor’s instructions to use hydroquinone cream, azelaic acid ointment and other drugs, can effectively reduce melanin deposition. 3. Chronic eczema: chronic eczema may also cause itching black thighs, patients should avoid rubbing, scratching the affected area. You can follow the doctor’s instructions to use topical dinexed, mometasone furoate and other glucocorticoid drugs, with anti-itching, anti-allergic effect. At the same time can follow the doctor’s instructions to take niacinamide, tranexamic acid and other drugs, can inhibit melanin production, reduce hyperpigmentation. 4. Ringworm: ringworm caused by fungal infection, local erythema itching, often scratching and friction after the local skin lesions pigmentation manifestation of black, the treatment of antifungal drugs such as topical terbinafine ointment, the serious can be orally itraconazole capsules and so on. The specific need to comply with the doctor’s prescription medication. Itchy thighs on both sides of the black cause more, in the exclusion of physiological factors, it is recommended to go to the regular hospital for examination, clear cause, with the doctor standardized treatment, do not blindly deal with their own.