Figure 9.3 Absorption of propranolol from nasal, intravenous and oral formulations cyclic impairments of one activity will be compensated for by an improvement in the other, thus helping to preserve the nasal defence mechanism.
Currently, intranasal drug delivery is primarily employed to treat allergies and infections which cause nasal irritation, sneezing and congestion by the topical action of drugs. The observation that nasally-administered sympathomimetics and antihistamines, used for their local action, produced quite significant systemic effects, suggested that the nasal route could be used effectively to deliver drugs systemically. Much recent research has focused on delivery of large molecules via this route, particularly peptides and proteins.
The intranasal route is very useful for avoiding injections in the young and is a good way of administering drugs to the elderly. Small drugs are absorbed rapidly, at rates comparable to intravenously administered drugs (Figure 9.3). However, the physiological conditions of the nose (vascularity, speed of mucus flow, retention and atmospheric conditions) will affect the efficacy of drugs or vaccines, as will the nature of the formulations, e.g. volume, concentration, density, viscosity, pH, tonicity, and pharmacological and immunological activity. The slower the clearance of the drug, the longer the time available for drug action or absorption.
Was this article helpful?
Download this Guide and Discover 50 Ways To Treat Acne Using Only Natural Remedies. About Time You Got Rid of Your Acne? Inside this guide, you'll discover: 50 ways to treat acne using natural remedies. The benefits of treating acne using natural remedies. Natural acne remedies to treat acne scarring. The side effects of popular acne medicines and treatments plus much, much more.