Liquid dosage forms: suspensions and emulsions 2

What 2 formulation considerations of physical properties must we take in?

Particle size and wetting properties of drug

Particle size

Wetting properties of drug

Crystal growth

What 2 vehicles can be used for pharmaceutial oral suspensions?

Purified water USP, buffers (citrate commonly used)

In pharmaceutical oral suspensions why do we add excipients?

To physically stabilise suspensions; control of rate of particle/floccule sedimentation

What are the 3 excipients we can add?

Addition of electrolytes, surface active agents and hydrophilic polymers

Addition of electrolytes

Surface active agents

For surface-active agents which one do we prefer?

Non-ionic as ionic surfactants have a greater toxcicity

Hydrophilic polymers

Preservatives

For the manufacture of suspensions for oral administration what are the 2 methods?

Direct incorporation and precipitation method

Direct incorporation

Percipitation method

What is meant by emulsions?

Disperse systems in which an insoluble liquid is dispersed in a second liquid phase

What are the 2 phases for emulsions?

Disperse and continuous phase

Disperse phase

Phase that is sub-divided

Continuous phase

Phase in which disperse phase is distributed

What are the 4 uses of emulsions?

What are 3 advantages of pharmaceutical emulsions?

What are another 3 advantages of pharmaceutical emulsions?

What are 2 disadvantages of pharmaceutical emulsions?

What are 3 types of emulsions?

What 6 things makes an acceptable emulsion/cream?

What is meant by emulsion type?

Defined by stability of droplet phase: of lower stability coalesces to form external phase

What are the 3 determinants for the type of emulsion produced?

Tests for identification of emulsion type