Pharmacy Drug Delivery Systems 5

Question 1

Which nasal drug delivery feature allows direct drug transport to the brain, bypassing the blood-brain barrier?

Accepted Answer

Nose-to-brain pathway via olfactory neurons

Answer

The olfactory and trigeminal nerve pathways in the nasal cavity allow direct drug transport to the CNS, bypassing the BBB.

Question 2

A matrix tablet formulated with HPMC releases drug by:

Accepted Answer

Erosion and diffusion through a gel layer

Answer

HPMC hydrates to form a viscous gel on contact with water; drug releases by diffusing through this gel and by gel erosion.

Question 3

For a drug to be suitable for pulmonary delivery to the deep lung, the aerodynamic particle size should be:

Accepted Answer

1–5 µm

Answer

Particles of 1–5 µm MMAD deposit in the alveolar region; larger particles impact in the upper airways and smaller ones are exhaled.

Question 4

Which statement about microemulsions is TRUE?

Accepted Answer

They are thermodynamically stable, clear systems with droplet size 10–100 nm

Answer

Microemulsions form spontaneously and are thermodynamically stable, with very small (10–100 nm) isotropic droplets that appear clear.

Question 5

An implantable drug delivery device made of ethylene-vinyl acetate (EVA) releases drug by:

Accepted Answer

Diffusion through the non-degradable polymer matrix

Answer

EVA is a non-biodegradable polymer; drug molecules diffuse through the polymer matrix down the concentration gradient.

Pharmacy Practice Test