Evaluation of Five Ready-to-Use Bases for the Topical Administration of Propranolol Hydrochloride to Treat Infantile Hemangioma

Background/Objectives: Since 2008, following clinical studies conducted on children that revealed the ability of the beta-adrenergic antagonist propranolol to inhibit capillary growth in infantile hemangiomas (IHs), its oral administration has become the first-line treatment for IHs. Although oral propranolol therapy at a dosage of 3 mg/kg/die is effective, it can cause systemic adverse reactions. This therapy is not necessarily applicable to all patients. Topical skin applications could help maintain a high drug concentration at local sites and also represent a characteristically easy method of administration for pediatric patients. Because no topical propranolol dosage forms are commercially available, such formulations may be prepared at hospitals and pharmacies. Methods: In the present study, we identified a simple method for preparing topical propranolol hydrochloride formulations at 1% w/w with five commercial ready-to-use bases and evaluated the pharmaceutical profiles. The physical stability of the extemporaneous formulations was predicted by performing an accelerated centrifuge test and assessed by visual inspection after one month storage at 25 degrees C. The chemical stability of the drug in the five formulations was assessed by using a high-performance liquid chromatography (HPLC) method. In vitro drug-release and permeability experiments were conducted through synthetic membranes and the outer pavilion of a pig's ear by utilizing Franz-type diffusion cells. Results: The results indicated that the release of the drug was significantly influenced by the internal structure and physicochemical properties of each base. Conclusions: Specifically, the formulations prepared with the hydrophilic bases could be easily prepared and yield satisfactory results, representing a potential effective therapy for IHs in pediatric patients.