A row of small blisters appeared on the waist.

A row of small blisters appearing around the waist is usually caused by conditions such as eczema, folliculitis, or allergic dermatitis. Patients should use medications under a doctor's guidance. Specific analyses are as follows:

1. Eczema

This is commonly associated with factors such as excessive sweating in the waist area or exposure to allergens. It manifests as red papules or blisters on the skin surface, accompanied by symptoms like itching and stinging. In such cases, patients should follow medical advice to apply topical medications such as tacrolimus ointment or halometasone cream.

2. Folliculitis

When hair follicles in the waist area become infected, red papules or vesicles may develop at the follicular sites, accompanied by symptoms including redness, swelling, exudation, and tenderness. Patients can use topical medications such as erythromycin ointment or fusidic acid cream as directed by a physician.

3. Allergic Dermatitis

This is often related to recent contact with or ingestion of allergenic substances. Skin lesions typically present as blisters or erythematous patches, accompanied by intense itching, fever, and other discomforts. Under medical supervision, patients may apply topical treatments such as compound acetic acid dexamethasone cream or calamine lotion to alleviate symptoms.

Besides the common causes mentioned above, other possible conditions include papular urticaria, tinea corporis, or herpes zoster. Patients experiencing such symptoms should promptly seek care at a reputable medical facility and pay attention to proper care of the affected area, avoiding excessive scratching.