1. SUPPOSITORIES - Definition - merits - limitations - formulations
- suppository bases
- compounding
- labeling
- displacement value
- evaluation

2. - solid or stiffened semi-solid dosage form for insertion into body cavities other than mouth
Types
Rectal
Vaginal (pessaries)
Urethral bougies
Ear (ear cones)
Nose bougies

3. Merits:
Local effects
Systemic effects
Mechanical effects
Bye pass first pass metabolism
Alternative route for unconscious, elderly patients etc
Unpleasant drugs
Avoids gastric irritation & GI instability
Prolonged drug release

4. Limitations:
Aesthetic objection
Leakage
Unpredictable absorption
Mucosal damage
Formulation:
Drug
Base
Other additives – surfactants, soothing agents, antioxidants, preservatives, anti-settling agents (blend of higher m.p waxes & fatty acids )

5. Methods of preparation:
Hand rolling method (trituration)
Moulding method (fusion)
Cold compresion method
Labeling:
- For rectal use only
- Store in a cool dry place or
- To be refrigerated etc

6. Ideal properties of a suppository base:
Easily melt and dissolve or disperse
Release medicament readily
Retain shape while handling
Non-toxic & non-irritant
Stable & compatible
Moldable, non adhering

7. Bases:
I. Oleaginous (fatty) bases
a) Natural - cocoa butter or their substitutes
b) Synthetic - witepsol, massuppol
II. Hydrophilic (water soluble/miscible) bases
a) Natural - glycero gelatin
b) Synthetic - macrogols
Cocoa butter:
m.p 30 – 36oc
Readily liquefiable on warming and rapid setting on cooling
Blandness

8. Limitations:
Polymorphism – unstable gamma/beta forms
Adhere to mould due to contractility on solidification
Softening point too low for hot climates (beeswax may be added)
Batch to batch variation in composition
Becomes rancid on storage
Immiscible in body fluids and poor water absorption
Tendency to leak, immiscibility makes it not suitable for vaginal and urethral route
May melt at warmer climates

9. Synthetic bases:
- readily available
- do not become rancid
- chemically more inert
- do not exhibit polymorphism
- good water absorption and emulsification properties
- lubrication can be avoided
- white, smooth & odorless
- may become brittle & fracture if cooled rapidly

10. Glycero-gelatin:
- may cause irritation due to dehydration of mucosa
- hygroscopic, careful storage
- incompatible with many drugs
- chance for microbial growth
- base preparation is time consuming
- sticky, can’t be used for hand rolling

11. Macrogols:
- combination for adjusting m.p, hardness etc
- may produce irritation due to hygroscopic nature
- suitable for tropical climates
- good solvent properties
- less liable to leakage due to high viscosity
- do not become rancid
- physiologically inert
- do not support microbial growth
- give clean & attractive suppositories
- form complex with some drugs & retard release

12. Displacement value:
- the number of parts by weight of drug that displaces one part of base.
Calculation of DV:
Wt. of 6 CB suppository, WCB
Wt. of 6 medicated(40%) suppository, WMS
Wt. of drug in suppository, WD = WMS x 40/100
Wt. of CB in suppository, WB = WMS – WD
Wt. of CB displaced by drug, WDCB = WCB – WB
Displacement value, DV = WD /WDCB

13. Evaluation:
- appearance
- wt. variation
- content uniformity
- melting temp.
- drug release
- stability studies