Hi and thanks for the query, The characteristics of the blisters give a good orientation on the specific diagnosis. Whether they are painful or not, itchy or not, it gives an orientation. The spreading of the lesions and the characteristics is very important. Recurrent rashes could demand a serious evaluation. Exposures to particular allergens or specific environmental conditions could lead to continuous recurrence of similar rash each time the allergen is contacted. A complete evaluation and examination of these lesions to actually detect the actual nature of these rashes and their characteristics might be helpful for a long term and effective management. Consult your primary care physician and possibly your dermatologist. Thanks and best regards, Luchuo, MD.