Topical Treatment of Infantile Haemangiomas: A Comparative Study on the Selection of a Semi-Solid Vehicle

<b><i>Background/Aim:</i></b> Topical β-blockers have recently been proposed as a valid alternative to oral drugs for treating cutaneous infantile haemangiomas, but clinical results in the literature are inconsistent due to the empirical choice of topical preparations. The current investigation aimed to rationalize the selection of a semi-solid vehicle for a locally applied drug product containing 1% w/w propranolol hydrochloride (PR-Cl). <b><i>Methods:</i></b> A hydrophobic ointment of PR-Cl, two lipophilic creams, and a hydrophilic cream were prepared. In vitro release and skin permeation studies through human epidermis and full-thickness skin were performed by Franz diffusion cells. <b><i>Results:</i></b> The overall results highlighted that PR-Cl was able to permeate the human epidermis, and its penetration pattern was strongly influenced by the composition of the semi-solid vehicle. PR-Cl release and permeation from lipophilic vehicles were extremely limited and influenced by their composition. Best results were obtained by using the hydrophilic cream. Furthermore, the retention study evidenced that epidermis acted as a reservoir, releasing the PR-Cl accumulated after preparation removal. <b><i>Conclusion:</i></b> The 1% w/w PR-Cl cream resulted the most suitable formulation for improving drug permeation through the human epidermis. On the contrary, the negligible permeation profile through full-thickness skin pointed out that PR-Cl cannot diffuse significantly to reach the deeper layers of human skin.