Taste Masking of Clarithromycin using Complexation with Ion exchange resin

Clarithromycin, an antibacterial agent, is extremely bitter in taste. The present research communication deals with development of taste masked resinate of clarithromycin using Tulsion-335, an acidic cation ion exchange resin. The drug resin complexes were prepared by batch process by taking drug to resin ratios of 1:1, 1:2, 1:3 and 1:4. The drug resin complexation procedure was optimized with respect to parameters like selection of suitable resin, mixing time, drug to resin ratio, effect of pH on drug loading and taste of complex. The drug resinate were evaluated for the drug content, taste, drug release and molecular properties. The resinate formation was confirmed using the techniques of Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). There is very little or no bitterness imparted with drug resin complexes with reference to pure drug. Dissolution rate studies of the taste masked drug resin complexes were carried out in Phosphate buffer pH 6.8 (Salivary pH). Dissolution rate studies in phosphate buffer pH 6.8 showed that more than 75 % of pure drug was dissolved in 10 minutes, while in the same period the dissolution of clarithromycin from drug resin complex in 1:3 ratio was below 50%. The dissolution of clarithromycin is thus reduced at salivary pH from the resinate. This reduction of dissolution rate of clarithromycin from the resinate is responsible for reduction of the bitterness of drug. These finding can be utilized to formulate a non bitter dosage form for clarithromycin without affecting the rate of dissolution.