Pharmaceutics Flashcards
7 cards from real FPGEE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Pharmaceutics flashcards as text
Which excipient acts as both a binder and a disintegrant in direct compression tablet formulations?
Answer: Microcrystalline cellulose (MCC)
MCC provides excellent binding under compression and also promotes disintegration via wicking and swelling mechanisms.
The Henderson-Hasselbalch equation predicts that a weak acid drug with pKa 4.0 in gastric fluid (pH 1.0) will be predominantly:
Answer: Unionized
When pH is much lower than pKa for a weak acid, the drug exists predominantly in the unionized form, favoring gastric absorption.
A transdermal drug delivery system is designed to deliver drug at a constant rate through the skin. This BEST describes which type of system?
Answer: Membrane-controlled (reservoir) system
Reservoir (membrane-controlled) transdermal systems use a rate-controlling membrane to deliver drug at a near-constant (zero-order) rate.
Which sterilization method is MOST suitable for heat-labile ophthalmic solutions?
Answer: Filtration through 0.22 μm membrane
Membrane filtration through a 0.22 μm filter removes microorganisms without exposing heat-labile drugs to high temperatures.
Which phenomenon occurs when two incompatible drugs are mixed in solution and form an insoluble complex that precipitates?
Answer: Incompatibility precipitation
Incompatibility precipitation results from a chemical reaction between two drug components or a drug and excipient, forming an insoluble product.
The concept of 'apparent volume of distribution' (Vd) in pharmacokinetics relates to:
Answer: Hypothetical volume in which the drug would need to be dissolved to achieve observed plasma concentration
Vd is a theoretical volume relating total drug in the body to plasma drug concentration; high Vd indicates extensive tissue distribution.
Which particle size reduction technique is MOST appropriate for producing nanosized drug particles (< 500 nm)?
Answer: High-pressure homogenization
High-pressure homogenization can reduce drug particle size to the nanometer range, producing nanosuspensions with improved dissolution.