Inner thigh hyperpigmentation may be caused by physiological factors such as friction, or it may be caused by post-inflammatory hyperpigmentation, acanthosis nigricans and other diseases, and patients can choose general treatment, medication and other ways to improve. 1. Physiological factors: If the inner thigh hyperpigmentation is caused by friction, patients should keep the skin clean and dry, and wear loose clothing to reduce local friction. 2. Post-inflammatory hyperpigmentation: Post-inflammatory hyperpigmentation may cause inner thigh hyperpigmentation, patients should avoid wearing tight clothes. You can also use azelaic acid and nicotinamide drugs to inhibit the proliferation of melanocytes, or use tretinoin and deoxyarbutin to inhibit the production of melanin and achieve the effect of lightening hyperpigmentation. 3. Acanthosis nigricans: Acanthosis nigricans may also cause hyperpigmentation on the inner thighs of patients, patients should pay attention to personal hygiene, keep the skin clean and dry. Cod liver oil ointment, hydroquinone cream and other drugs can also be applied on the affected area to reduce the inner thigh hyperpigmentation. There are more reasons for inner thigh hyperpigmentation, after excluding physiological factors, it is recommended to go to a regular hospital and choose the appropriate removal method under the guidance of the doctor. The medication should be used according to the doctor’s prescription.