Avens (Geum urbanum), also known as herb Bennet, has a history of use in traditional herbal medicine, particularly in Europe. Historical records and herbal texts from the Middle Ages indicate that Avens was applied externally in poultices or washes to promote wound healing and to soothe skin irritations, including blisters. The plant contains tannins, which are compounds known for their astringent properties. These astringents can help to dry out and protect the skin, potentially aiding in the healing process of minor blisters and reducing inflammation.

However, scientific research specifically evaluating the efficacy of Avens for treating blisters is lacking. Most available evidence is anecdotal or based on traditional herbal practices rather than rigorous clinical studies. The traditional use of Avens for skin conditions is primarily justified by its content of tannins and some antimicrobial compounds, which might theoretically support minor wound care. Nonetheless, there is insufficient high-quality scientific data to confirm its effectiveness for this particular indication.

In summary, Avens is used for blisters based on traditional and historical herbal practices, with a low level of supporting evidence and no direct scientific validation for this specific use.