Tinea cruris is a skin disease caused by fungal infections such as Trichophyton rubrum, Trichophyton rubrum, Trichophyton rubrum, and Candida albicans. The main site of occurrence is the moist, sweaty area at the root of the inner thighs, which can spread to the scrotum and buttocks. The lesions appear as round or irregular-shaped erythematous plaques, or papules and papules, followed by desquamation, and the lesions gradually expand and may fuse and overlap with each other, forming irregular rings, semi-rings, and maps with clear boundaries due to self-healing in the central part. Pruritus is obvious, and frequent scratching can lead to secondary skin mossiness, which thickens and darkens the skin. Direct microscopic examination of the fungus by scraping the scales from the marginal active lesions can find mycelium. The fungus can be found in the lesions and in the underwear, which can cause contact infection. Long-time drivers, fat people, workers in hot and humid environments, diabetics, and bedridden people are susceptible. When the above situation is found, do not just go to the pharmacy to buy drugs, but should promptly go to the hospital for examination, after a clear diagnosis of the available antifungal topical drugs, and in serious cases also need to be combined with oral antifungal drugs under the guidance of doctors. Introduce a simple external treatment method: 20g of hibiscus bark, 20g of bupleurum and 15g of bitter ginseng, decocted in water and washed externally, 1-2 times a day. After external washing, use one of the selected ciclopirox ointment, lamisul cream, miconazole nitrate cream for external use 1-2 times a day. The disease is similar to eczema, interscalene dermatitis, and diaper rash performance. If mistakenly treated with corticosteroid-containing creams, although the itch can be temporarily stopped, but the fungus will grow more and more, and the lesions will become larger and larger. The skin of the femur is thin and should not be treated with creams that have an irritating and exfoliating effect. Proper treatment should also pay attention to keep the femur breathable and dry, do not wear tight underwear, underwear often disinfected with boiling water. If you also have fungal infections in other areas (such as gray nails and ringworm), you should also actively treat them to prevent mutual infection.