Google 上搜 small itchy blisters on hands。湿疹的一种

https://www.medicalnewstoday.com/articles/321733.php

A person with dyshidrotic eczema, also called foot-and-hand eczema or pompholyx, will notice tiny, itchy, fluid-filled blisters on their hands, fingers and often toes and feet. This condition is thought to be associated with stress, skin irritants, and seasonal allergies. ...