Pharmaceutical Suspensions Quiz

12 Questions

What is the primary reason for using solvents in suspensions?

To serve as the base for dispersing solid particles

Which of the following best describes the result of sedimentation in un-flocculated suspensions?

Slower settling and potential cake formation

What is the primary role of emulsifiers in the administration of oil-soluble drugs?

To improve the solubility and absorption of the drug

Which theory explains how emulsifying agents prevent the coalescence of dispersed phase droplets in emulsions?

Oriented-wedge theory

What is the dispersion medium in an emulsion?

The continuous phase in which the dispersed phase is suspended

What is the primary advantage of using complex or multiple emulsions in drug formulations?

Improved patient compliance

What is the primary reason suspensions are preferred as a dosage form?

All of the above

Which of the following factors does not affect the sedimentation rate in suspensions?

Temperature

What is the main difference between flocculated and un-flocculated suspensions?

Flocculated suspensions settle faster

What is the role of suspending agents or viscosity modifiers in pharmaceutical suspensions?

Increase the viscosity to slow down sedimentation

What happens when suspensions are allowed to stand for a prolonged period?

Sedimentation occurs, leading to phase separation

Which of the following is not a disadvantage of suspensions as a medication form?

Poor solubility of the drug

Study Notes

Suspensions in Pharmaceuticals

Uniform distribution, slow settling, and quick re-dispersion are ensured through solvents, which serve as the base for dispersion of solid particles.
Sedimentation theory explains the factors affecting the rate of sedimentation of particles, including particle size, density difference, medium viscosity, and external forces.
The primary benefit of using complex suspensions is improved patient compliance, and they are preferred as a dosage form due to poor solubility, controlled release, taste masking, convenience, and swallowing difficulty.

Emulsions in Pharmaceuticals

Emulsions are viscous multiphase systems with dispersed liquids, and the dispersion medium is the continuous phase in which the dispersed phase is suspended.
Emulsifying agents prevent the coalescence of dispersed phase droplets through the oriented-wedge theory, and they improve solubility and absorption of oil-soluble drugs.
Emulsions can be classified based on their composition as oil-in-water (O/W) or water-in-oil (W/O), and they benefit food products by enhancing texture and shelf life.

Additives in Suspensions

Flavoring agents, sweeteners, and colorants enhance taste, palatability, and aesthetics in medications.
Buffering agents control pH changes in the formulation, and humectants and chelating agents inhibit evaporation and prevent degradation.
Emulsifiers and surfactants improve distribution of particles for homogeneity, decrease interfacial tension, and prevent coalescence in emulsions.
Suspending agents/viscosity modifiers increase viscosity to decrease sedimentation.

Characterization of Suspensions

Suspensions are biphasic liquid preparations, heterogeneous mixtures with particles larger than 1 µm, and can be classified based on concentration, electrokinetic properties, and particle size.
The advantages of suspensions as a medication form include higher bioavailability, improved stability, controlled release, and taste masking.
The desired features of suspensions are uniform distribution, slow settling, quick re-dispersion, efficacy, stability, and taste.

Limitations of Suspensions

Physical instability, sedimentation, uneven dosing, bulkiness, and unpleasant texture are the disadvantages of suspensions as a medication form.
When suspensions are allowed to stand, sedimentation occurs, leading to phase separation.