Unit14PharmaceuticsII

• Emulsifying agents
• Wetting agents
• ex. polysorbate 20

• To promote and maintain dispersion of finely subdivided particles of liquid in a vehicle in which it is immiscible (oil and water)
• ex. Sodium lauryl sulfate, lanolin, cetyl ROH, acacia, Glyceryl monostearate

• Aid in attaining intimate contact between solid particles and a liquid
• ex. Polysorbate, Sodium lauryl sulfate, Benzalkonium chloride

• Liquid used as an intervening agent to reduce the particle size of a powder by grinding (usually in a mortar)- makes paste usually
• Mineral oil, glycerin, propylene glycol

• Used to increase thickness or hardness of a preparation
• (i.e. ointments)
• ex. Ceresin, Stearyl alcohol

• Used to soften the skin and make it more pliable
• ex. Mineral Oil, petrolatum, lanolin

• Used to provide an acidic medium for product stability
• ex. Citric acid – also used as an antioxidant, buffering agent, chelating agent, and flavor enhancer

• Used to resist change in pH upon dilution or addition of acidic or alkali agents
• ex. Potassium phosphate, monobasic, and sodium acetate

• Inert filler to create desired bulk and flow properties
• Also aids in compression characteristics of tablets and capsules
• ex. lactose, mannitol, sorbitol, starch

• Used in liquid and semisolid preparations to prevent growth of microorganisms
• ex. Imidurea, sodium acetate, sodium benzoate, parabens, ROH

• Used to render preparations more resistant to flow
• • In suspensions to deter sedimentation
• • In ophthalmic solutions to increase contact time
• • To thicken topical creams
• ex. Carbomer – gelling agent

• —Scientific study of deformation and flow properties of matter
• Applied to solids, liquids and gases

viscosity and elasticity

Measure of resistance to flow or thickness

• Measure of stretchiness or structure
• Predominantly solid feature

greater the resistance of the material to flow

• Phenomenon observed in materials exhibiting both elastic behavior and viscous flow
• i.e. polymer gel, gelatin

dispensing and formulation of various dosage forms including emulsions, suspensions, creams, lotions and tablet coatings

• Passage through the orifices, including pouring, packaging in bottles
• Passage through hypodermic needles.
• Removal from jars and extrusion from tubes
• Spreading and adherence to the skin
• Capacity of solids to mix with miscible liquids
• Release of drug from the base

• Thixotropic materials become more fluid with increasing time of applied force (stirring, pumping, shaking)
• Often reversible

asymmetric particles that provide a loose three dimensional structure via numerous points of contact throughout the sample.

• Rest: structure provides a degree of rigidity on the system that resembles a gel
• Shear applied: the structure begins to breakdown as points of contact are disrupted and particles become aligned.

• Study of deformation and flow in biological systems
• Biological fluids are viscoelastic materials that are rheologically complex

is a non-Newtonian fluid and rheological properties of blood are influenced by many pathological conditions

• by hematocrit (Hct) and plasma viscosity.
• Elevated Hct is associated with arteriosclerosis, angina, myocardial infarction.

Final product should be pourable or injectable

• Addition of pharmaceutical additives could change the properties of the ointment base.
• Removal from container esp. important in case of elderly patients

Development of systems that gel in situ upon administration

• Used in preparations to provide alkaline medium for product stability
• ex. Triethanoloamine (trolamine)

Any component other than the active principle added intentionally to the medicinal formulation

• the physiochemical properties of pharmaceuticals
• Ensure the weight, consistency and volume necessary for proper dosage administration