In situ method to estimate local effect of nasal preparations
The potential local toxicity to the respiratory mucosa of drugs, excipients and formulations should be tested in an appropriate animal model. Today: many models are available for such studies, giving different information. Since the mucociliary clearance is one of the most important defence mechanism of the human body against inhaled dust, allergens and microorganisms this mechanism may not be alTected or destroyed. Environmental conditions, such as humidity, temperature,
airborne toxins, as well as chemicals and many pharmaceutical excipients affects this mechanism. This review gives a short insight into this field, focusing mainly on the frog palate model, Where the effect of drugs on the mueoeiliary transport rate may be studied.