Dense small rashes on the roots of the thighs may be a symptom caused by eczema, jock itch and other diseases. Patients should undergo general treatment, medication, etc. under the advice of a doctor. 1. Eczema: Eczema is a chronic inflammatory itchy skin disease. Patients may show symptoms such as red spots, pimples and itching. Thigh root eczema patients should pay attention to avoid scratching, less contact with chemical composition supplies. Patients with oozing can use 3% boric acid solution to apply wet compresses locally, and when there is no oozing, itch-relieving drugs such as glycerite lotion and glucocorticoid drugs such as hydrocortisone butyrate ointment can be used. If the external drug treatment is not effective, patients can take oral antihistamine drugs, such as loratadine. 2. Ringworm: Ringworm is a common fungal infection of the skin, which can be transmitted through direct or indirect contact. The surface of the skin lesions of patients can appear red spots, papules, flaking and other symptoms. Patients with tinea cruris should pay attention to keep the affected skin dry, and consume less food that is easy to sweat or spicy stimulation. Patients can use topical antifungal drugs, such as ketoconazole cream, econazole cream, terbinafine cream and so on. Patients with ineffective topical drug treatment can take oral itraconazole and other systemic treatment drugs. All of the above drugs should be used under the guidance of a doctor, and patients should not use them on their own to avoid delays. Patients with dense small rashes on the roots of the thighs should go to the hospital in a timely manner and be treated under the guidance of a doctor.