RESUMO
Mucoadhesive membranes were proposed in this study as drug delivery system for betamethasone-17-valerate (BMV) in the treatment of recurrent aphthous stomatitis (RAS). The membranes were obtained by using the polymers chitosan (CHI) in both presence and absence of polyvinilpyrrolidone (PVP), following the solvent evaporation method. The presence of PVP in the membranes causes significant modifications in its thermal properties. Changes in the thermal events at 114 and 193⯰C (related to BMV melting point), and losses in mass (39.38 and 30.68% for CH:PVP and CH:PVP-B, respectively), suggests the incorporation of BMV in these membranes. However, the morphological aspects of the membranes do not change after adding PVP and BMV. PVP causes changes in swelling ratios (>80%) of the membranes, and it is suggested that the reorganization of the polymer mesh was highlighted by the chemical interactions between the polymers leading to different percentages of BMV released â¼40% and â¼80% from CH-B and CH:PVP-B. BMV release profile follows Korsmeyer and Peppas model (nâ¯>â¯0.89) which suggests that the diffusion of the drug in the swollen matrix is driven by polymer relaxation. In addition, the membranes containing PVP (higher swelling ability) present high rates of tensile strength, and therefore, higher mucoadhesion. Moreover, given the results presented, the developed mucoadhesive membranes are a promising system to deliver BMV for the treatment of RAS.
RESUMO
PURPOSE: To compare the efficacy of three different formulations containing Betamethasone Valerate versus placebo in the topical treatment of phimosis. As a secondary goal, we compared the outcomes after 30 and 60 days of treatment. MATERIALS AND METHODS: Two hundred twenty boys aged 3 to 10 years old with clinical diagnosis of phimosis were enrolled. Patients were randomized to one of the following groups: Group 1: Betamethasone Valerate 0.2 percent plus Hyaluronidase; Group 2: Betamethasone Valerate 0.2 percent; Group 3: Betamethasone Valerate 0.1 percent or Group 4: placebo. Parents were instructed to apply the formula twice a day for 60 days and follow-up evaluations were scheduled at 30, 60 and 240 days after the first consultation. Success was defined as complete and easy foreskin retraction. RESULTS: One hundred ninety-five patients were included at our final analysis. Group 1 (N = 54), 2 (N = 51) and 3 (N = 52) had similar success and improvement rates, all treatment groups had higher success rates than placebo(N = 38). After 60 days of treatment, total and partial response rates for Groups 1, 2 and 3 were 54.8 percent and 40.1 percent, respectively, while placebo had a success rate of 29 percent. Success and improvement rates were significantly better in 60 days when compared to 30 days. CONCLUSIONS: Betamethasone Valerate 0.1 percent, 0.2 percent and 0.2 percent in combination with Hyaluronidase had equally higher results than placebo in the treatment of phimosis in boys from three to ten years-old. Patients initially with partial or no response can reach complete response after 60 days of treatment.