D 3 Flashcards
What are the different types of powder based medicines
Bulk and wrapped powders
Capsules
Tablets
Oral bulk powders
Packed in jars
Spoonfuls of powder dispersed in water or etc
Easy to take
Useful when drug is unstable in water
Wrapped powders and sachets
Single dose of powder mixture packed in a small bag
More accurate and convenient
Better protection against moisture
Why oral bulk and wrapped powders
For patients who have difficulty swallowing
More stable that liquid medicines
Good way to give large doses by mouth
Fast dissolution = fast action
What are the issues with powders
1 moisture
Absorb water ( hygroscopic)
Can dissolve during processing and storage
Caking
SO MUST BE PROTECTED AGAINST MOISTURE
Issues with powders 2
- Flow
Poor flow will lead to inaccurate / inconsistent packing
Size, shape, surface charge affect flow ability - Mixing and separation
Poor mixing will lead to inaccurate dosing
Powder mixes can unmix during movements
How to solve mixing and separation issues
Equalise particles sizes
Mix equal amounts if powders
Granulation ( bounding particles together to form larger particles)
Can be packed into bulk containers
Filled into capsules
Compressed into tablets
Types of excipients
Bulking agents
Granulating agents (binders)
Effervescent mixtures
Flow aid
Anti caking agents
Surfactants
Flavours ; colours
What are capsules filled of
Powder mixtures
Granules
Small tablets
Combination
Why hard capsules
Easy to swallow
Different sizes available
Shell protects powder and masks taste
Shell can be coloured
Can be coated for delayed release
Easier to manufacture
Soft capsules
One piece shell made Of gelatine
Used for oils , liquids and semi solids
Larger than capsules but easier to swallow
Tablets
Small and portable
Very stable
Shape and colour give distinction
How are tablets made
From granules or powder mixtures by compression on high speed tablet
What do compression aids / binders do
Bind particles under pressure to make tablets stronger
Lubricants
Help tablet machine eject tablet after compression
Tablet coat
Protect contents from water air and oxygen
Taste masking
Identification
Disintegrants
Break the tablet in the stomach by attracting water and making it swell
Dispersible
Dissolved in water before taking or on tongue
Quick acting
Contain an effervescent mixture
Immediate release
Conventional tablets
Disintegrate and release drug in stomach
Fast action
Delayed release
Remain intact in the stomach disintegrate in small intestine
Used if drug irritates stomach
Coats is insoluble in acid but soluble in neutral ph
Extended release
Slowly release drug in GI tract over 8-24h
Used if only one dose a day is required and fast drug release cause side effects
Tablets designed with either a coating insoluble but porous or a matrix that erodes slowly
