Thin polymeric films for the topical delivery of propranolol.

BACKGROUND/AIMS: Infantile hemangioma (IH), the most common benign tumor of childhood, is currently treated with propranolol. The aim of this work was to study in vitro propranolol permeation and skin retention from an original polymeric film, composed of polyvinyl alcohol and an acrylic polymer.

METHODS: Propranolol polymeric films were applied in occlusive and non-occlusive conditions, on either full thickness skin or isolated epidermis. Experiments were performed also on stripped skin, to simulate the skin permeability of damaged skin.

RESULTS: The results obtained underline the importance of determining skin concentration when dealing with drugs that should act on the skin. Skin permeation data are a poor predictor of skin retention data, in particular in critical conditions, such as heavily damaged skin.

CONCLUSION: The film proposed for the treatment of IH (and other vascular diseases) with propranolol seems to be a good alternative to semisolid formulations, in particular if used in non-occlusive conditions, because it guarantees high proportions of drug retained in the skin, compared to permeated across the skin, reducing the risks of systemic side effect.