Oral Capsules Flashcards
What are capsules?
Solid preparations with hard or soft shells of various shapes + capacities, containing single dose of active substances
What are advantages of capsules?
Easier to swallow than tablets Easier to handle + carry Easy to identify wide range of colours Tasteless Required minimal excipients Minimal pressure to compact High drug loading possible (up to 90%)
What are disadvantages of capsules?
Not suitable for highly soluble substances
Not suitable for highly deliquescent materials
High product cost
Why are capsules not suitable for highly soluble substances?
Can cause sudden release in stomach = irritation
Why are capsules not suitable for highly deliquescent materials?
May dry shell = brittleness
What are the different types of capsules?
Cachets Hard capsules Soft capsules Gastro-resistant capsules Modified-release capsules
What are hard + soft capsules made form?
Gelatin
How many pieces are hard capsules?
2
How many pieces are soft capsules?
1
How is gelatin made?
Hydrolysis of collagen from connective tissues
Made form calf bones + pig skin
What is the acid process for producing gelatin?
Animal collagen Acidification pH 4 Heating from 50 degrees to boiling Elimination of fate Filtration Vacuum evaporation Drying
How long does acid process take?
7-10 days
What does the acid process produce?
Type A gelatin
What is the alkali process for producing gelatin?
Animal collagen Treatment with NaOH Remove NaOH Treatment with acid to adjust pH Heating from 50 degrees to boiling Demineralisation Filtration Vacuum evaporation Drying
How long does alkali process take?
70-100 days
What does the alkali process produce?
Type B gelatin
What are the properties of gelatin?
Non-toxic + non-irritant
Soluble in biological fluids at body temp
Good film forming properties
Solutions of high conc mobile at 50 degrees
Change to a gel above RT
What are the problems with gelatin?
Gelatin allergy
Vegans + vegetarians
Why are colourants added?
Improve patient compliance
Medication identification
Phycological effect
Potential for light protection
What are the two types of colourants?
Water soluble dyes
Insoluble pigments
Why are optional materials added?
Process aids - eg. surfactants
Preservatives
Performance aids - eg. flavouring agent
Describe hard capsule
Most common
Consist of cap + body
Filled with drug
How many sizes of hard capsules are available?
8
What must hard capsule filling be?
Free form large amount of moisture Not react with shell Not leak out Have good powder flow Not be adhesive Be capable of being filled uniformly
Why are diluents added in hard capsules?
Bulk forming properties
Why are lubricants added in hard capsules?
Reduce powder to metal adhesion
Why are glidants added in hard capsules?
Reduce powder cohesion
Why are wetting agents added in hard capsules?
Improve H2O penetration
Why are stabilisers added in hard capsules?
Improve product stability
Why are disintegrates added in hard capsules?
Produce disruption of powder mass
How are hard capsules filled?
Empty capsules orientated in correct position
2 halves separated
Exact dose places onto surface of body plate + spread with spatula to fill capsule
Cap locked on body
Filled capsule removed from machine
What does soft capsules consist of?
Liquid or semisolid matrix sealed inside one-piece flexible solid-phase gelatin shell
What are the advantages of soft capsules?
Increase rate of absorption Tasteless Easy to swallow Enhanced safety Dose uniformity Product stability
Why are soft capsules increased rate of absorption?
Already solution
Why do soft capsules have enhanced safety?
No airborne powder during manufacturing
Why is it good that soft capsules have dose uniformity?
Better homogeneity + flow than powder
Why are soft capsules more stable?
Drug protected by shell + lipid vehicles
Against oxidation, moisture, ect
What are the types of soft capsules?
Oral soft capsules Chewable Twist-off Suckable Meltable
What are the composition of soft capsules?
Gelatin (40%)
Plasticizers (20-30%)
H2O
Why are plasticizers used?
Make shell soft + pliable
Why is H2O used?
Allow proper processing during gel preparation + soft gel encapsulation
What are the different types of softgel fill matrices?
Lipophilic liquid
Hydrophilic liquid
Self-emulsifying liquid
Why are lipophilic liquid used?
For lipophilic drugs
eg. vitamin D + steroids
Why are self-emulsifying liquid used?
Auto emulsifies to form droplets when in contact with GI fluid
Allow greater capacity to solubilise drug
High SA of droplet facilitate rapid diffusion of drug
What do self-emulsifying liquid contain?
oil + surfactant
What is an example of lipophilic liquid?
Triglyceride oils
What is an example of hydrophilic liquid?
Polyethene glycol
How are softgels manufactured?
Fully automated machine
