Multi-Dose Container for Nasal and Ophthalmic Drugs: A Preservative Free Future?

The first nasal spray pumps were developed some 50 years ago and replaced step by step droppers and pipettes. Now they are widely used to moisturize the nasal mucosa using saline solutions (from a regulatory point of view considered medical devices under the EU directive) or as nasal preparations for the administration of topically acting drugs (e.g. nasal decongestants or nasal steroids) or for the non-invasive administration of substances which need to reach systemic circulation (anti-migraine medication, hormones). For chronic diseases like allergic rhinitis, multi-dose devices are very cost effective and convenient and provide the safety and precision regulatory bodies require. To date, most of the medications administered nasally contain a preservative to support long storage times and proper in-use stability. For ophthalmic drugs, there was a similar development from simple droppers to more sophisticated devices. Squeeze bottles without metering function are still widely used for ophthalmic medications especially for chronic conditions. Artificial tears filled in multi-dose bottles are commonly used to relieve dry eye symptoms, these again being medical devices because the mode of action is purely physical. Looking at active drugs, the most successful in the ophthalmic field are drugs (e.g. beta-antagonists and prostaglandine-analogues) for the treatment of glaucoma and anti-histamines to treat allergic conjunctivitis. The reader may wonder why nasal spray pumps together with multi-dose ophthalmic droppers are considered in the very same chapter. The answer is that both device classes share the same blueprint: they use a bottle made of plastic or glass attached to a pump or dropper which generates and delivers a more or less metered dose and on top of this serves as a closure. So the pumps or droppers support two general functions: Sealing of the container and protection of the content during storage and transportation. Delivery of a metered dose of liquid or viscous pharmaceutical formulation. The major challenge during development is to reach a reliable delivery of the metered dose without having any negative impact caused by drug-device interactions.