The formulation and evaluation of salbutamol dry powder inhalation mixtures with the Rotahler device

Metered dose inhalers (MDIs) contain chlorofluorocarbons, widely known, to affect the environment adversely. These chemicals deplete the ozone layer. The use of dry powder inhalers is therefore in the ascendance to replace MDIs for delivery of medicines to the respiratory tract. In this study we have formulated dry powder inhalation mixtures containing salbutamol sulphate  using recrystallised lactose or modified lactose prepared by a proprietary method to smoothen the surface texture of the lactose. The effect of the proprietary method used to smoothen the surface texture of the recrystallized lactose was evaluated with the ROTAHALERTM device and the Twin Impinger BP in deposition tests. The respirable fraction obtained was higher in inhalation mixtures containing the recrystallized lactose compared to those containing regular lactose used as basis for comparison. Keywords: formulation, salbutamol, evaluation, powder, inhalation, Rotahaler