KOFIS Flashcards
What is suspension
Preparation where you can see particulates , at least one active ingredient, each drop has equal amounts.
Oral liquid
-Ready made
-Reconstituted- like antibiotics-come as powders you add water, and it turns into
the medicine
-Suspension- shake well before use
-Dosing accuracy- use syringe -most accurate way- make sure you have the right
dose
What are some su
Why is particle size important
Slow rate of sedimentation (small- harder for drug to sink at the bottom) (large- heavier so sink at the bottom quicker)
Storage
Advantages of suspensions
Draggability, swallobitility, absorption and modification of drug release
Disadvantages of suspensions
Patient compliance- have to shake before use
Dosing accuracy -less accurate than solutions
Storage conditions effect of disperse system
Transportation- can be bulky heavy or leak
Suspension formulation
Controlled flocculations -have lose drug particles that can be easily distributed before dispensing
-system is controllably flocculated to ensure the formulation is redispersed before
use
• Structured vehicle/solution
-increase viscosity to reduce sedimentation
-use polymers to reduce rate of sedimentation for suspended drug particles
-polymer added to increase viscosity
2 types of controlled flocculations
Indiffusible suspension:
contains light insoluble powders
when shaken disperse evenly throughout the vehicle
long enough to allow for an accurate dose to be poured out
some examples can include: light magnesium carbonate BP, magnesium trisilicate BP
Diffusible suspension:
Contains heavy insoluble powders
When shaken don’t disperse evenly throughout the vehicle
long enough to allow an accurate dose to be poured, therefore vehicle is thickened (requires a suspending agent) to slow down the rate of sedimentation, viscosity and particle size
some examples can include: aspirin BP, Calamine BP, gaviscon
Suspending Agents (have to know 2 of each)
natural polysaccharides: acacia gum bp, starch bp,
semi-synthetic polysaccharides: methyl cellulose bp, sodium carboxy methyl cellulose BP
Clays: aluminium magnesium silicate bp, bentonite bp
synthetic: carbomer Bp, polyvinyl alcohol bp
others: gelatin bp
Polymers
Polymers are defines as long chain molecules that can be made or occur naturally
generally rope like molecules that are made by joining many monomers (single) together
types of polymers: linear, branched, crosslinked
can be either chemical or physical
Conditions for bridging flocculation
good absorbers, good solvent, very low polymer density, and long polymers, polymers can be formed between particles and they can also form flocs
Examples of flavourings (need to know 1 of each)
flavoured syrups: blackcurrant syrup bp
aromatic waters: concentrated peppermint water bp
spirits: lemon spirit bp
extracts: liquid liquorice extract bp
topical formulations
composed of drug in a suitable semi-solid base
drug is suspended or dissolved in a semi-solid base
base could be either hydrophobic or hydrophilic
base plays role in drug release behaviour
if hydrophobic or hydrophilic base is chosen, drug release is different depending on each
Drugs are
dissolved or-completely mixed into ointment
dispersed in the-drug molecules suspended in base
ointment base-are greasy and is immiscible
ointment bases are
Anhydrous-contains no H2O
Greasy
Immiscible with skin secretions-so can be hard to apply because when you sweat, the sweat will form atop and adsorb to the surface
mixture of waxes (solid at rt), fats (semisolid at rt), oils (liquid at rt)
preparation of ointments
fusion
melt base in water bath
high mp to low mp
as base coold, add ingredients with decreasing mp
stir continuously (homogenous mix)
leave to set
