Pediatric drug formulations of sodium benzoate:: I.: Coated granules with a hydrophilic binder

High doses of sodium benzoate are applied in the treatment of some rare metabolic disorders. In most cases children are affected who often refuse the oral uptake of sodium benzoate as a powder or in solution due to its bad taste. Therefore, small-sized, saliva-resistant microcapsules have been developed containing high doses of the drug substance. Granules were produced by roller compacting of sodium benzoate powder without any additives, by solvent-free cold extrusion and hot-melt extrusion adding poly(ethylene glycol)s of different grades. The granules with a diameter of less than 1 mm were film-coated by an ethanolic solution of Eudragit(R) E 100. The microcapsules from hot-melt extrusion containing 25% Macrogol 4000 were most stable during the coating process and showed the highest yields. Sodium benzoate is completely released from the microcapsules within 9 min into 0.1 N HCl and 0.01 N HCl whereas dissolution into buffer pH 6.8 is different in the initial phase and completed after 14 min. The bad taste of sodium benzoate is not recognized in the buccal space for at least 5 min. The microcapsules are stable during storage for at least 6 months. (C) 2003 Elsevier B.V. All rights reserved.