Lec 12- Suppositories Flashcards
Suppositories
Solid dosage form for insertion into rectum where they melt or soften to allow active ingredient (s) to exert local or systemic effects
Pessaries
Vaginal administration - usually for local effect
Advantages of rectal administration
- Not exposed to degradation by gastric acid
- No direct irritation to stomach
- First pass metabolism is avoided
- For patients who cannot swallow or are vomiting
Ideal suppository base
- Melt at just below body temperature
- Solidify quickly after melting
- Be easy to mould and remove from mould
- Be chemically stable even when molten
- Release the active ingredient readily
- Be easy to handle
- Be non-toxic and non-irritant
2 examples of fatty bases
- Natural Theobroma Oil
2. Synthetic Novata B
2 examples of water soluble and water-miscible bases
- Gelatin bases
2. Macrogols
Displacement value
Number of parts, by weight of drug which displaces one part by weight of base
How to make suppositories
- Grate base, only to give accurate weight
- Over water bath, heat until 2/3 melted
- Place insoluble powders on tile
- Add half of the molten mixture
- Mix with spatula, then return to heat to re-melt if necessary
- Remove from heat, stir until almost set
- Overfill the moulds (contracts on cooling)
- Scrape off excess when set towards you with a warmed spatula so don’t chip suppositories
- Unscrew, tap gently on bench to open
Packaging of suppository
Wrap individually in foil
Pack into cardboard skillet and label
Labelling of suppository
For rectal use only, do not swallow
Store in a cool dry place
Expiry: one month
Patient advice: unwrap and insert into rectum