Hello, thank you for consulting with healthcaremagic. As you are mentioning that your husband is suffering from a medical condition, in which he gets blisters on his gums. If it is so recurrent, then you should consult a good oral medicine specialist. But still you can use steroids, but it should be used after consulting a good specialist, as here we cannot diagnose the condition. For proper treatment you suould visit him and get it properly examined. Hope it will help you.