Prolonged exposure to a humid environment may cause the following three diseases. The first disease is eczema, which can cause a local allergic reaction in a humid environment, resulting in erythema, papules, papules, blisters, vesicles, exudates, crusts, and is accompanied by itching. In clinical treatment, oral levocetirizine hydrochloride capsules and topical application of 2% boric acid solution can be used for treatment. The second condition is caused by fungal infections, which are particularly prone to breeding in humid environments. If fungus is produced to cause ringworm and tinea corporis, topical terbinafine hydrochloride gel is needed for treatment. The third condition is that long-term exposure to a humid environment is prone to psoriasis, and if psoriasis is produced, it can be treated by applying carbotriol ointment.