Reduced Environmental Impact of the Reusable Respimat® Soft Mist™ Inhaler Compared with Pressurised Metered-Dose Inhalers

INTRODUCTION

Pressurised metered-dose inhalers (pMDIs) are associated with global warming potential values as they contain a hydrofluoroalkane (HFA) propellant, whereas the Respimat^® Soft Mist™ inhaler is propellant-free. The original disposable Respimat has recently been updated to provide a reusable device that is similar in performance and use but is more convenient to patients and reduces environmental impact. This study compared the product carbon footprint (PCF) of Respimat (both disposable and reusable) and pMDIs to understand life cycle hotspots, and also to determine the potential quantitative environmental benefits of a reusable Respimat product.

METHODS

PCFs of four inhalation products-tiotropium bromide (Spiriva^®) Respimat, ipratropium bromide/fenoterol hydrobromide (Berodual^®) Respimat, Berodual HFA pMDI and ipratropium bromide (Atrovent^®) HFA pMDI-were assessed across their whole life cycle.

RESULTS

Data show that Respimat inhalers have a lower PCF (carbon dioxide equivalent per kilogram) than HFA pMDIs: pMDI Atrovent 14.59; pMDI Berodual 16.48; disposable Spiriva Respimat 0.78; disposable Berodual Respimat 0.78. Approximately 98% of the pMDI life cycle total is due to HFA propellant emissions during use and end-of-life phases. The impact of the material used for the Respimat product outweighs the impact of the material used to make the empty cartridge. Furthermore, compared with the single-use device over 1 month, the PCF of Spiriva Respimat was further reduced by 57% and 71% using the device with refill cartridges over 3 and 6 months, respectively.

CONCLUSION

Together, these data suggest that Respimat inhalers, and in particular the new reusable inhaler, can reduce the environmental impact associated with inhaler use.

FUNDING

Boehringer Ingelheim.

The suppressive effects of recombinant human tumor necrosis factor-alpha on normal and malignant myelopoiesis: synergism with interferon-gamma

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Assessment of left ventricular function from the mitral valve echocardiogram following positive and negative inotropic interventions

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