Preparation and Evaluation of Matrix Tablets Containing Ambroxol Hydrochloride

Purpose: This study aimed to formulate Ambroxol hydrochloride SR matrix tablets using xanthan gum (natural polymer) and to elucidate the release kinetics of Ambroxol hydrochloride from xanthan gum-matrices. Methods: controlled release matrix tablets of ambroxol hydrochloride, a mucolytic expectorant  were prepared by wet granulation method using xanthan gum as natural hydrophilic polymer in three different ratios (Drug : Polymer 1:1(F-1), 1:1.5(F-2), 1:2(F-3)). The prepared granules of three different formulations were evaluated for angle of repose, bulk density (BD), tapped density (TD) and compressibility index (CI), hausners ratio. The prepared tablets were tested for physical parameters like weight variation, hardness, friability, content of active ingredient and In-vitro drug release studies. Results: The results obtained were within the prescribed limits. The release of ambroxol from the matrix tablets was sustained up to 12hrs. The cumulative percentage of drug release was decrease with increase in polymer concentration. Among the three formulations F-3 gave the release profile close to the commercially available marketed sample of ambroxol Hcl (A-MS).The results indicate that the drug release from the matrix tablets followed Zero order kinetics. The dissolution data was fitted to Korsmeyer equation which is used to describe the drug release behaviour from polymeric systems. All the formulations showed diffusion co-efficient value (n) greater than 0.43 but less than 0.85 after fitting to the Korsmeyer equation. So, it indicates Non-Fickian transport mechanism. Therefore the drug release is by diffusion and erosion mechanism. Conclusion: Matrix tablets of Ambroxol Hydrochloride using xanthan gum prepared by wet granulation method were found to be good in appearance. The drug-polymer ratio was found to influence the release of drug from the formulations. Formulation F-3 i.e. (1:2 drug: polymer) exhibited the similar In-vitro drug release rates as that of the marketed sample.