Drug Delivery Systems Flashcards

Which parameter is MOST critical when designing a transdermal patch for a drug with high molecular weight?

Answer: Skin permeation enhancement

High molecular weight drugs penetrate skin poorly, so permeation enhancers are critical for effective transdermal delivery.

A drug formulated as a liposome is BEST described as:

Answer: A phospholipid bilayer vesicle encapsulating drug

Liposomes are closed phospholipid bilayer vesicles that can encapsulate both hydrophilic and hydrophobic drugs.

Which route of administration completely bypasses first-pass metabolism?

Answer: Intravenous

Intravenous administration delivers drug directly to systemic circulation, entirely bypassing hepatic first-pass metabolism.

An osmotic pump tablet (OROS) releases drug primarily by:

Answer: Osmotic pressure driving drug through a laser-drilled orifice

OROS tablets use osmotic pressure built up by water influx to push drug solution through a precisely drilled delivery orifice.

Which excipient class is commonly used in hot-melt extrusion to improve drug solubility?

Answer: Enteric polymers like HPMC-AS

HPMC-AS and similar polymers form solid dispersions via hot-melt extrusion, improving the solubility of poorly water-soluble drugs.

Mucoadhesive drug delivery systems are designed primarily to:

Answer: Prolong contact time with mucosal membranes

Mucoadhesive systems use polymers that adhere to mucosal surfaces, extending residence time and improving drug absorption.

A nanoparticle drug carrier with a size of 10–200 nm is MOST likely to accumulate in tumor tissue via:

Answer: Enhanced permeability and retention (EPR) effect

The EPR effect allows nanoparticles to passively accumulate in tumors due to leaky vasculature and poor lymphatic drainage.