4.4 Intranasal (4) Flashcards
When we spray the drug through the nose (Vestibule) the drug is going to deposit on the _____
epithelia of the turbinates
Vestibular region consist of nasal vestibule and valve, main function is to filter air with long hairs and vestibule communicates to the nasal cavity through the ____ (a narrow passage).
Nasal Valve
_____ turbinate has less physiological significance than the other two turbinates.
Superior
bc air passes through the lower turbinates
Turbinates direct heat (make warmer), and humidify incoming air, increase surface area, and promote ____
turbulence
increase particle impaction-trap in the nasal cavity
The ______ region is the major region for drug absorption.
Respiratory
The _______ region has small surface area, its the roof of the nasal cavity, poorly ventilated, and close to CNS.
Olfactory
Posterior (2/3) of respiratory region has _____ epithelium.
ciliated pseudostratified columnar
Anterior (1/3) of respiratory region has various epithelia that goes from outside to inside the body:
squamous-Transitional-Pseudostratified Columnar
Posterior of respiratory region with its pseudostratified columnar epithelia (goblet cells) is responsible for ________ Clearance.
Mucociliary
mechanism in removing undissolved drug by moving the suspended drug in the mucus and by moving the mucus with cilia
Mucus is continuously removed posteriorly by cilia except forward in the anterior region of the _____ turbinate.
inferior
Clearance of inhaled substances from the nose within _____ minutes (narrow window of time before drug is removed).
15-20
______ turbinate communicates with the nasolacrimal duct.
Inferior
______ turbinate communicates with several sinuses.
Middle
The presence and fluidity of mucus are vital for ciliary function, if the mucus is too viscous, the ciliary movement and clearance are (slowed or increased)
slowed
Nasal enzymatic activity is a component of clearance and it is (more or less) than in small intestines.
Less
Transporters are efflux systems expressed in the nasal epithelium, and an example is …
p-glycoprotein
Respiratory region is highly vascularized epithelium with fenestrated capillaries, thus good for systemic purposes and allowing (smaller or larger) molecules. It is not drained to the hepatic portal system (bypass hepatic 1st pass)
larger
Drops give greater nasal coverage but are cleared more (slowly or rapidly)
rapidly
Particles (aerosol droplets) of about ____ in diameter in size for impact, thus, the important size range for drug delivery
8-20 microns
larger particles=impaction
Intranasal drug delivery can be good alternative for _____ because of its immune function e.g. Nasal Associated Lymphoid Tissue (NALT) ex. Flumist
Vaccinations
Inflammation, fever, asthma, nasal polyps are examples of changes in architecture of nasal cavity which affect drug ..
absorption, deposition, and/or clearance
Environmental conditions ( humidity, temperature, and some drugs with anticholinergic) may dry nasal secretions and affect _____ function
mucociliary
Intranasal vasoconstrictor (e.g. Afrin) can (improve or reduce) systemic bioavailability.
reduce
Ciliary movement is slower below the pH of ____
7