The formulation and evaluation of terbutaline sulphate and dry powder inhalation mixtures with the rotahaler device

Abstract

The formulation of the dry powder inhalers generally involves the production and characterization of a powder suitable for respiratory deposition and the formulation with or without excipients in a device. The drug formulation consists of micronised drug/s or mixtures of drug/s and carrier. A flow aid may be an additional component of the drug formulation. The formulation is usually prepackaged in unit doses or as a bulk, from which portions are dispensed. Though there have been significant advances, especially in understanding the role of carrier properties on the aerosol performance of the drug, the exact mechanism of adhesion and drug liberation during aerosolization is still not clearly understood and is a major focus among researchers within the field. In this study we report the use of low rugosity lactose, productof controlled crystallization of this carrier, in the formulation of terbutaline sulphate dry powder inhaler. The respirable fraction or the amount of emitted terbutaline sulphate available for deposition in the lungs for therapeutic action is higher in inhalation mixtures containing this modified lactose compared to regular lactose BP used as basis for comparison.

Keywords: Dry powder inhaler, terbutaline sulphate, modified lactose, Rotahaler device, respirable fraction