In Situ Gelling Dexamethasone Oromucosal Formulation: Physical Characteristics Influencing Drug Delivery

Area of Science:

• Pharmaceutical Sciences
• Materials Science
• Biomedical Engineering

Background:

• Aphthous stomatitis causes significant oral discomfort and pain.
• Current treatments for aphthous stomatitis have limitations in efficacy and delivery.
• Oromucosal drug delivery systems offer potential for localized and sustained treatment.

Purpose of the Study:

• To develop and characterize an in situ gelling oromucosal formulation for dexamethasone (DEX) delivery.
• To evaluate the impact of essential oil (EO) and solubilization on formulation properties.
• To assess the mucoadhesive, physical, and in vitro release characteristics of the developed system.

Main Methods:

• Preparation of three series of DEX oromucosal formulations with varying polymers and mint EO.
• Evaluation of physical properties: pH, rheology, swelling, and texture analysis.
• In vitro drug release studies, hen's egg test on the chorioallantoic membrane (HET-CAM) for irritation, and Fourier-transform infrared spectroscopy (FT-IR) for compatibility.

Main Results:

• The hydroxypropyl methylcellulose (HPMC)-based formulation with mint EO and propylene glycol (PG) showed optimal swelling (700 ± 46%) and drug release (34.7 ± 5.9%).
• The formulation exhibited adequate mucoadhesive properties and low irritancy potential (HET-CAM).
• FT-IR analysis confirmed no chemical incompatibility between DEX and the formulation excipients.

Conclusions:

• In situ gelling mucoadhesive systems show promise for enhanced oromucosal drug delivery of dexamethasone.
• The developed HPMC-based formulation offers a potentially effective and safe treatment for aphthous stomatitis.
• Optimized formulation design can improve therapeutic efficacy for managing painful oral lesions.