Formulation, Optimization and Evaluation of Medicated Chewing Gum for Combination

Abstract

The objective of the present work was to formulate a medicated chewing gum for combination therapy. Dextromethorphan HBr is an NMDA antagonist which suppresses the urge to cough and provide relief from dry, sticky coughs. Promethazine HCl is an antihistamine which works by blocking the effects of histamine and dries secretions in the nose and used for relief of symptoms associated with the common cold. Thus, it was decided to develop a suitable combination formulation for the treatment of upper respiratory infections. Medicated chewing gum (MCG) was prepared in view to avoid first pass metabolism, better patient compliance and stability. MCG was prepared using direct compression method. Estimation of the concentration of both drugs was done using Simultaneous Equation method. Drug - drug and drug – excipients compatibility studies were carried out using FTIR and DSC. Taste masking was achieved successfully in both the drugs using Aspartame, Peppermint flavour, and Menthol. Effect of Gum base concentration, Aerosil and Sorbitol, Softening agent were also studied. Central Composite Design was used to evaluate the effects of amount of gum base and concentration of softening agent as independent variables while hardness (Peak Load), and time required to release 85% of the drug (t85) were selected as dependent variables. MCG was coated to prevent it from accidental shock and to enhance the aesthetic appearance. Results of in vivo human study revealed that MCG prepared had good taste, chewablity and softness. The 85% drug release after coating for DXM and PMZ was achieved within 21 minutes and 23 minutes respectively. The study shown that use of combination therapy is boon for the patients suffering from upper respiratory infections.