Inhalation unit-dose systems

Early dry powder inhaler devices were all unit-dose systems and depended on loading and triggering procedures. The Spinhaler and Rotahaler are two early examples of DPI technology. Both utilize premetered doses packed into hard gelatin capsules although different mechanisms of powder delivery are employed ... 

Inhance Pulmonary Delivery System Inhale Unit dose Mechanical, not driven by patient inspiration = =... 

Inhalation solution and suspension drug products are typically aqueous-based formulations that contain therapeutically active ingredients and can also contain additional excipients. Aqueous-based oral inhalation solutions and suspension must be sterile (21 CFR 200.51). Inhalation solutions and suspensions are intended for delivery to the lungs by oral inhalation for local or systemic effects and are used with a specified nebulizer. Unit-dose presentation is recommended for these drug products to prevent microbial contamination during use. The container closure system for these drug products consists of the container and closure and can include protective packaging such as foil overwrap. 

The active inhaler made by Nektar Therapeutics (formerly Inhale Therapeutic Systems, United States), called Pulmonary Delivery System (PDS), mechanically compresses a fixed volume of air required for delivery and dispersion of a premetered dry-powder unit dose by a spring-loaded pump (Fig. 8.10). Generation of the respirable aerosol cloud thus is independent of the inspiration effort exerted by the patient. The aerosol is generated in a transparent holding chamber that acts as a spacer from which the patient inhales the standing cloud of particles (Patton 1997). The PDS device is actually close to market for inhaled delivery of insulin under the trade name Exubera. 

The Solo device from Inhale Therapeutic Systems is a patient-driven unit dose inhaler. It has a built-in flow control to maximize the reproducibility of dose to patient. It is designed for short-term use and when large drug dosages are preferred. 

The AERx, developed by Aradigm (Hayward, CA), is a metered dose liquid inhaler designed to deliver various pharmaceutical compounds to the peripheral lungs. The system, as shown in Fig. 10, consists of a unit dose disposable container equipped with a nozzle array, a piston assembly, and electronics associated with breath actuation and compliance monitoring functions. ... 

External dose, as used in the report, refers to the amount of chemical that is inhaled, is ingested, or comes in dermal contact and is available for systemic absorption. External dose is typically expressed in units of milligrams of chemical per kilogram of body weight per day (mg/kg/day). 

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